Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

26 files changed, 4728 insertions, 0 deletions

diff --git a/toolkit/components/contentprefs/ContentPrefService2.sys.mjs b/toolkit/components/contentprefs/ContentPrefService2.sys.mjs
new file mode 100644
index 0000000000..43fa0c4cb6
--- /dev/null
+++ b/toolkit/components/contentprefs/ContentPrefService2.sys.mjs
@@ -0,0 +1,1468 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import {
+  ContentPref,
+  cbHandleCompletion,
+  cbHandleError,
+  cbHandleResult,
+} from "resource://gre/modules/ContentPrefUtils.sys.mjs";
+
+import { ContentPrefStore } from "resource://gre/modules/ContentPrefStore.sys.mjs";
+
+const lazy = {};
+ChromeUtils.defineESModuleGetters(lazy, {
+  Sqlite: "resource://gre/modules/Sqlite.sys.mjs",
+});
+
+const CACHE_MAX_GROUP_ENTRIES = 100;
+
+const GROUP_CLAUSE = `
+  SELECT id
+  FROM groups
+  WHERE name = :group OR
+        (:includeSubdomains AND name LIKE :pattern ESCAPE '/')
+`;
+
+export function ContentPrefService2() {
+  if (Services.appinfo.processType === Services.appinfo.PROCESS_TYPE_CONTENT) {
+    return ChromeUtils.importESModule(
+      "resource://gre/modules/ContentPrefServiceChild.sys.mjs"
+    ).ContentPrefServiceChild;
+  }
+
+  Services.obs.addObserver(this, "last-pb-context-exited");
+
+  // Observe shutdown so we can shut down the database connection.
+  Services.obs.addObserver(this, "profile-before-change");
+}
+
+const cache = new ContentPrefStore();
+cache.set = function CPS_cache_set(group, name, val) {
+  Object.getPrototypeOf(this).set.apply(this, arguments);
+  let groupCount = this._groups.size;
+  if (groupCount >= CACHE_MAX_GROUP_ENTRIES) {
+    // Clean half of the entries
+    for (let [group, name] of this) {
+      this.remove(group, name);
+      groupCount--;
+      if (groupCount < CACHE_MAX_GROUP_ENTRIES / 2) {
+        break;
+      }
+    }
+  }
+};
+
+const privModeStorage = new ContentPrefStore();
+
+function executeStatementsInTransaction(conn, stmts) {
+  return conn.executeTransaction(async () => {
+    let rows = [];
+    for (let { sql, params, cachable } of stmts) {
+      let execute = cachable ? conn.executeCached : conn.execute;
+      let stmtRows = await execute.call(conn, sql, params);
+      rows = rows.concat(stmtRows);
+    }
+    return rows;
+  });
+}
+
+/**
+ * Helper function to extract a non-empty group from a URI.
+ * @param {nsIURI} uri The URI to extract from.
+ * @returns {string} a non-empty group.
+ * @throws if a non-empty group cannot be extracted.
+ */
+function nonEmptyGroupFromURI(uri) {
+  if (uri.schemeIs("blob")) {
+    // blob: URLs are generated internally for a specific browser instance,
+    // thus storing settings for them would be pointless. Though in most cases
+    // it's possible to extract an origin from them and use it as the group.
+    let embeddedURL = new URL(URL.fromURI(uri).origin);
+    if (/^https?:$/.test(embeddedURL.protocol)) {
+      return embeddedURL.host;
+    }
+    if (embeddedURL.origin) {
+      // Keep the protocol if it's not http(s), to avoid mixing up settings
+      // for different protocols, e.g. resource://moz.com and https://moz.com.
+      return embeddedURL.origin;
+    }
+  }
+  if (uri.host) {
+    // Accessing the host property of the URI will throw an exception
+    // if the URI is of a type that doesn't have a host property.
+    // Otherwise, we manually throw an exception if the host is empty,
+    // since the effect is the same (we can't derive a group from it).
+    return uri.host;
+  }
+  // If reach this point, we'd have an empty group.
+  throw new Error(`Can't derive non-empty CPS group from ${uri.spec}`);
+}
+
+function HostnameGrouper_group(aURI) {
+  try {
+    return nonEmptyGroupFromURI(aURI);
+  } catch (ex) {
+    // If we don't have a host, then use the entire URI (minus the query,
+    // reference, and hash, if possible) as the group.  This means that URIs
+    // like about:mozilla and about:blank will be considered separate groups,
+    // but at least they'll be grouped somehow.
+
+    // This also means that each individual file: URL will be considered
+    // its own group.  This seems suboptimal, but so does treating the entire
+    // file: URL space as a single group (especially if folks start setting
+    // group-specific capabilities prefs).
+
+    // XXX Is there something better we can do here?
+
+    try {
+      return aURI.prePath + aURI.filePath;
+    } catch (ex) {
+      return aURI.spec;
+    }
+  }
+}
+
+ContentPrefService2.prototype = {
+  // XPCOM Plumbing
+
+  classID: Components.ID("{e3f772f3-023f-4b32-b074-36cf0fd5d414}"),
+
+  // Destruction
+
+  _destroy() {
+    Services.obs.removeObserver(this, "profile-before-change");
+    Services.obs.removeObserver(this, "last-pb-context-exited");
+
+    // Delete references to XPCOM components to make sure we don't leak them
+    // (although we haven't observed leakage in tests).  Also delete references
+    // in _observers and _genericObservers to avoid cycles with those that
+    // refer to us and don't remove themselves from those observer pools.
+    delete this._observers;
+    delete this._genericObservers;
+  },
+
+  // in-memory cache and private-browsing stores
+
+  _cache: cache,
+  _pbStore: privModeStorage,
+
+  _connPromise: null,
+
+  get conn() {
+    if (this._connPromise) {
+      return this._connPromise;
+    }
+
+    return (this._connPromise = (async () => {
+      let conn;
+      try {
+        conn = await this._getConnection();
+      } catch (e) {
+        this.log("Failed to establish database connection: " + e);
+        throw e;
+      }
+      return conn;
+    })());
+  },
+
+  // nsIContentPrefService
+
+  getByName: function CPS2_getByName(name, context, callback) {
+    checkNameArg(name);
+    checkCallbackArg(callback, true);
+
+    // Some prefs may be in both the database and the private browsing store.
+    // Notify the caller of such prefs only once, using the values from private
+    // browsing.
+    let pbPrefs = new ContentPrefStore();
+    if (context && context.usePrivateBrowsing) {
+      for (let [sgroup, sname, val] of this._pbStore) {
+        if (sname == name) {
+          pbPrefs.set(sgroup, sname, val);
+        }
+      }
+    }
+
+    let stmt1 = this._stmt(`
+      SELECT groups.name AS grp, prefs.value AS value
+      FROM prefs
+      JOIN settings ON settings.id = prefs.settingID
+      JOIN groups ON groups.id = prefs.groupID
+      WHERE settings.name = :name
+    `);
+    stmt1.params.name = name;
+
+    let stmt2 = this._stmt(`
+      SELECT NULL AS grp, prefs.value AS value
+      FROM prefs
+      JOIN settings ON settings.id = prefs.settingID
+      WHERE settings.name = :name AND prefs.groupID ISNULL
+    `);
+    stmt2.params.name = name;
+
+    this._execStmts([stmt1, stmt2], {
+      onRow: row => {
+        let grp = row.getResultByName("grp");
+        let val = row.getResultByName("value");
+        this._cache.set(grp, name, val);
+        if (!pbPrefs.has(grp, name)) {
+          cbHandleResult(callback, new ContentPref(grp, name, val));
+        }
+      },
+      onDone: (reason, ok, gotRow) => {
+        if (ok) {
+          for (let [pbGroup, pbName, pbVal] of pbPrefs) {
+            cbHandleResult(callback, new ContentPref(pbGroup, pbName, pbVal));
+          }
+        }
+        cbHandleCompletion(callback, reason);
+      },
+      onError: nsresult => {
+        cbHandleError(callback, nsresult);
+      },
+    });
+  },
+
+  getByDomainAndName: function CPS2_getByDomainAndName(
+    group,
+    name,
+    context,
+    callback
+  ) {
+    checkGroupArg(group);
+    this._get(group, name, false, context, callback);
+  },
+
+  getBySubdomainAndName: function CPS2_getBySubdomainAndName(
+    group,
+    name,
+    context,
+    callback
+  ) {
+    checkGroupArg(group);
+    this._get(group, name, true, context, callback);
+  },
+
+  getGlobal: function CPS2_getGlobal(name, context, callback) {
+    this._get(null, name, false, context, callback);
+  },
+
+  _get: function CPS2__get(group, name, includeSubdomains, context, callback) {
+    group = this._parseGroup(group);
+    checkNameArg(name);
+    checkCallbackArg(callback, true);
+
+    // Some prefs may be in both the database and the private browsing store.
+    // Notify the caller of such prefs only once, using the values from private
+    // browsing.
+    let pbPrefs = new ContentPrefStore();
+    if (context && context.usePrivateBrowsing) {
+      for (let [sgroup, val] of this._pbStore.match(
+        group,
+        name,
+        includeSubdomains
+      )) {
+        pbPrefs.set(sgroup, name, val);
+      }
+    }
+
+    this._execStmts([this._commonGetStmt(group, name, includeSubdomains)], {
+      onRow: row => {
+        let grp = row.getResultByName("grp");
+        let val = row.getResultByName("value");
+        this._cache.set(grp, name, val);
+        if (!pbPrefs.has(group, name)) {
+          cbHandleResult(callback, new ContentPref(grp, name, val));
+        }
+      },
+      onDone: (reason, ok, gotRow) => {
+        if (ok) {
+          if (!gotRow) {
+            this._cache.set(group, name, undefined);
+          }
+          for (let [pbGroup, pbName, pbVal] of pbPrefs) {
+            cbHandleResult(callback, new ContentPref(pbGroup, pbName, pbVal));
+          }
+        }
+        cbHandleCompletion(callback, reason);
+      },
+      onError: nsresult => {
+        cbHandleError(callback, nsresult);
+      },
+    });
+  },
+
+  _commonGetStmt: function CPS2__commonGetStmt(group, name, includeSubdomains) {
+    let stmt = group
+      ? this._stmtWithGroupClause(
+          group,
+          includeSubdomains,
+          `
+        SELECT groups.name AS grp, prefs.value AS value
+        FROM prefs
+        JOIN settings ON settings.id = prefs.settingID
+        JOIN groups ON groups.id = prefs.groupID
+        WHERE settings.name = :name AND prefs.groupID IN (${GROUP_CLAUSE})
+      `
+        )
+      : this._stmt(`
+        SELECT NULL AS grp, prefs.value AS value
+        FROM prefs
+        JOIN settings ON settings.id = prefs.settingID
+        WHERE settings.name = :name AND prefs.groupID ISNULL
+      `);
+    stmt.params.name = name;
+    return stmt;
+  },
+
+  _stmtWithGroupClause: function CPS2__stmtWithGroupClause(
+    group,
+    includeSubdomains,
+    sql
+  ) {
+    let stmt = this._stmt(sql, false);
+    stmt.params.group = group;
+    stmt.params.includeSubdomains = includeSubdomains || false;
+    stmt.params.pattern =
+      "%." + (group == null ? null : group.replace(/\/|%|_/g, "/$&"));
+    return stmt;
+  },
+
+  getCachedByDomainAndName: function CPS2_getCachedByDomainAndName(
+    group,
+    name,
+    context
+  ) {
+    checkGroupArg(group);
+    let prefs = this._getCached(group, name, false, context);
+    return prefs[0] || null;
+  },
+
+  getCachedBySubdomainAndName: function CPS2_getCachedBySubdomainAndName(
+    group,
+    name,
+    context
+  ) {
+    checkGroupArg(group);
+    return this._getCached(group, name, true, context);
+  },
+
+  getCachedGlobal: function CPS2_getCachedGlobal(name, context) {
+    let prefs = this._getCached(null, name, false, context);
+    return prefs[0] || null;
+  },
+
+  _getCached: function CPS2__getCached(
+    group,
+    name,
+    includeSubdomains,
+    context
+  ) {
+    group = this._parseGroup(group);
+    checkNameArg(name);
+
+    let storesToCheck = [this._cache];
+    if (context && context.usePrivateBrowsing) {
+      storesToCheck.push(this._pbStore);
+    }
+
+    let outStore = new ContentPrefStore();
+    storesToCheck.forEach(function (store) {
+      for (let [sgroup, val] of store.match(group, name, includeSubdomains)) {
+        outStore.set(sgroup, name, val);
+      }
+    });
+
+    let prefs = [];
+    for (let [sgroup, sname, val] of outStore) {
+      prefs.push(new ContentPref(sgroup, sname, val));
+    }
+    return prefs;
+  },
+
+  set: function CPS2_set(group, name, value, context, callback) {
+    checkGroupArg(group);
+    this._set(group, name, value, context, callback);
+  },
+
+  setGlobal: function CPS2_setGlobal(name, value, context, callback) {
+    this._set(null, name, value, context, callback);
+  },
+
+  _set: function CPS2__set(group, name, value, context, callback) {
+    group = this._parseGroup(group);
+    checkNameArg(name);
+    checkValueArg(value);
+    checkCallbackArg(callback, false);
+
+    if (context && context.usePrivateBrowsing) {
+      this._pbStore.set(group, name, value);
+      this._schedule(function () {
+        cbHandleCompletion(callback, Ci.nsIContentPrefCallback2.COMPLETE_OK);
+        this._notifyPrefSet(group, name, value, context.usePrivateBrowsing);
+      });
+      return;
+    }
+
+    // Invalidate the cached value so consumers accessing the cache between now
+    // and when the operation finishes don't get old data.
+    this._cache.remove(group, name);
+
+    let stmts = [];
+
+    // Create the setting if it doesn't exist.
+    let stmt = this._stmt(`
+      INSERT OR IGNORE INTO settings (id, name)
+      VALUES((SELECT id FROM settings WHERE name = :name), :name)
+    `);
+    stmt.params.name = name;
+    stmts.push(stmt);
+
+    // Create the group if it doesn't exist.
+    if (group) {
+      stmt = this._stmt(`
+        INSERT OR IGNORE INTO groups (id, name)
+        VALUES((SELECT id FROM groups WHERE name = :group), :group)
+      `);
+      stmt.params.group = group;
+      stmts.push(stmt);
+    }
+
+    // Finally create or update the pref.
+    if (group) {
+      stmt = this._stmt(`
+        INSERT OR REPLACE INTO prefs (id, groupID, settingID, value, timestamp)
+        VALUES(
+          (SELECT prefs.id
+           FROM prefs
+           JOIN groups ON groups.id = prefs.groupID
+           JOIN settings ON settings.id = prefs.settingID
+           WHERE groups.name = :group AND settings.name = :name),
+          (SELECT id FROM groups WHERE name = :group),
+          (SELECT id FROM settings WHERE name = :name),
+          :value,
+          :now
+        )
+      `);
+      stmt.params.group = group;
+    } else {
+      stmt = this._stmt(`
+        INSERT OR REPLACE INTO prefs (id, groupID, settingID, value, timestamp)
+        VALUES(
+          (SELECT prefs.id
+           FROM prefs
+           JOIN settings ON settings.id = prefs.settingID
+           WHERE prefs.groupID IS NULL AND settings.name = :name),
+          NULL,
+          (SELECT id FROM settings WHERE name = :name),
+          :value,
+          :now
+        )
+      `);
+    }
+    stmt.params.name = name;
+    stmt.params.value = value;
+    stmt.params.now = Date.now() / 1000;
+    stmts.push(stmt);
+
+    this._execStmts(stmts, {
+      onDone: (reason, ok) => {
+        if (ok) {
+          this._cache.setWithCast(group, name, value);
+        }
+        cbHandleCompletion(callback, reason);
+        if (ok) {
+          this._notifyPrefSet(
+            group,
+            name,
+            value,
+            context && context.usePrivateBrowsing
+          );
+        }
+      },
+      onError: nsresult => {
+        cbHandleError(callback, nsresult);
+      },
+    });
+  },
+
+  removeByDomainAndName: function CPS2_removeByDomainAndName(
+    group,
+    name,
+    context,
+    callback
+  ) {
+    checkGroupArg(group);
+    this._remove(group, name, false, context, callback);
+  },
+
+  removeBySubdomainAndName: function CPS2_removeBySubdomainAndName(
+    group,
+    name,
+    context,
+    callback
+  ) {
+    checkGroupArg(group);
+    this._remove(group, name, true, context, callback);
+  },
+
+  removeGlobal: function CPS2_removeGlobal(name, context, callback) {
+    this._remove(null, name, false, context, callback);
+  },
+
+  _remove: function CPS2__remove(
+    group,
+    name,
+    includeSubdomains,
+    context,
+    callback
+  ) {
+    group = this._parseGroup(group);
+    checkNameArg(name);
+    checkCallbackArg(callback, false);
+
+    // Invalidate the cached values so consumers accessing the cache between now
+    // and when the operation finishes don't get old data.
+    for (let sgroup of this._cache.matchGroups(group, includeSubdomains)) {
+      this._cache.remove(sgroup, name);
+    }
+
+    let stmts = [];
+
+    // First get the matching prefs.
+    stmts.push(this._commonGetStmt(group, name, includeSubdomains));
+
+    // Delete the matching prefs.
+    let stmt = this._stmtWithGroupClause(
+      group,
+      includeSubdomains,
+      `
+      DELETE FROM prefs
+      WHERE settingID = (SELECT id FROM settings WHERE name = :name) AND
+            CASE typeof(:group)
+            WHEN 'null' THEN prefs.groupID IS NULL
+            ELSE prefs.groupID IN (${GROUP_CLAUSE})
+            END
+    `
+    );
+    stmt.params.name = name;
+    stmts.push(stmt);
+
+    stmts = stmts.concat(this._settingsAndGroupsCleanupStmts());
+
+    let prefs = new ContentPrefStore();
+
+    let isPrivate = context && context.usePrivateBrowsing;
+    this._execStmts(stmts, {
+      onRow: row => {
+        let grp = row.getResultByName("grp");
+        prefs.set(grp, name, undefined);
+        this._cache.set(grp, name, undefined);
+      },
+      onDone: (reason, ok) => {
+        if (ok) {
+          this._cache.set(group, name, undefined);
+          if (isPrivate) {
+            for (let [sgroup] of this._pbStore.match(
+              group,
+              name,
+              includeSubdomains
+            )) {
+              prefs.set(sgroup, name, undefined);
+              this._pbStore.remove(sgroup, name);
+            }
+          }
+        }
+        cbHandleCompletion(callback, reason);
+        if (ok) {
+          for (let [sgroup, ,] of prefs) {
+            this._notifyPrefRemoved(sgroup, name, isPrivate);
+          }
+        }
+      },
+      onError: nsresult => {
+        cbHandleError(callback, nsresult);
+      },
+    });
+  },
+
+  // Deletes settings and groups that are no longer used.
+  _settingsAndGroupsCleanupStmts() {
+    // The NOTNULL term in the subquery of the second statment is needed because of
+    // SQLite's weird IN behavior vis-a-vis NULLs.  See http://sqlite.org/lang_expr.html.
+    return [
+      this._stmt(`
+        DELETE FROM settings
+        WHERE id NOT IN (SELECT DISTINCT settingID FROM prefs)
+      `),
+      this._stmt(`
+        DELETE FROM groups WHERE id NOT IN (
+          SELECT DISTINCT groupID FROM prefs WHERE groupID NOTNULL
+        )
+      `),
+    ];
+  },
+
+  removeByDomain: function CPS2_removeByDomain(group, context, callback) {
+    checkGroupArg(group);
+    this._removeByDomain(group, false, context, callback);
+  },
+
+  removeBySubdomain: function CPS2_removeBySubdomain(group, context, callback) {
+    checkGroupArg(group);
+    this._removeByDomain(group, true, context, callback);
+  },
+
+  removeAllGlobals: function CPS2_removeAllGlobals(context, callback) {
+    this._removeByDomain(null, false, context, callback);
+  },
+
+  _removeByDomain: function CPS2__removeByDomain(
+    group,
+    includeSubdomains,
+    context,
+    callback
+  ) {
+    group = this._parseGroup(group);
+    checkCallbackArg(callback, false);
+
+    // Invalidate the cached values so consumers accessing the cache between now
+    // and when the operation finishes don't get old data.
+    for (let sgroup of this._cache.matchGroups(group, includeSubdomains)) {
+      this._cache.removeGroup(sgroup);
+    }
+
+    let stmts = [];
+
+    // First get the matching prefs, then delete groups and prefs that reference
+    // deleted groups.
+    if (group) {
+      stmts.push(
+        this._stmtWithGroupClause(
+          group,
+          includeSubdomains,
+          `
+        SELECT groups.name AS grp, settings.name AS name
+        FROM prefs
+        JOIN settings ON settings.id = prefs.settingID
+        JOIN groups ON groups.id = prefs.groupID
+        WHERE prefs.groupID IN (${GROUP_CLAUSE})
+      `
+        )
+      );
+      stmts.push(
+        this._stmtWithGroupClause(
+          group,
+          includeSubdomains,
+          `DELETE FROM groups WHERE id IN (${GROUP_CLAUSE})`
+        )
+      );
+      stmts.push(
+        this._stmt(`
+        DELETE FROM prefs
+        WHERE groupID NOTNULL AND groupID NOT IN (SELECT id FROM groups)
+      `)
+      );
+    } else {
+      stmts.push(
+        this._stmt(`
+        SELECT NULL AS grp, settings.name AS name
+        FROM prefs
+        JOIN settings ON settings.id = prefs.settingID
+        WHERE prefs.groupID IS NULL
+      `)
+      );
+      stmts.push(this._stmt("DELETE FROM prefs WHERE groupID IS NULL"));
+    }
+
+    // Finally delete settings that are no longer referenced.
+    stmts.push(
+      this._stmt(`
+      DELETE FROM settings
+      WHERE id NOT IN (SELECT DISTINCT settingID FROM prefs)
+    `)
+    );
+
+    let prefs = new ContentPrefStore();
+
+    let isPrivate = context && context.usePrivateBrowsing;
+    this._execStmts(stmts, {
+      onRow: row => {
+        let grp = row.getResultByName("grp");
+        let name = row.getResultByName("name");
+        prefs.set(grp, name, undefined);
+        this._cache.set(grp, name, undefined);
+      },
+      onDone: (reason, ok) => {
+        if (ok && isPrivate) {
+          for (let [sgroup, sname] of this._pbStore) {
+            if (
+              !group ||
+              (!includeSubdomains && group == sgroup) ||
+              (includeSubdomains &&
+                sgroup &&
+                this._pbStore.groupsMatchIncludingSubdomains(group, sgroup))
+            ) {
+              prefs.set(sgroup, sname, undefined);
+              this._pbStore.remove(sgroup, sname);
+            }
+          }
+        }
+        cbHandleCompletion(callback, reason);
+        if (ok) {
+          for (let [sgroup, sname] of prefs) {
+            this._notifyPrefRemoved(sgroup, sname, isPrivate);
+          }
+        }
+      },
+      onError: nsresult => {
+        cbHandleError(callback, nsresult);
+      },
+    });
+  },
+
+  _removeAllDomainsSince: function CPS2__removeAllDomainsSince(
+    since,
+    context,
+    callback
+  ) {
+    checkCallbackArg(callback, false);
+
+    since /= 1000;
+
+    // Invalidate the cached values so consumers accessing the cache between now
+    // and when the operation finishes don't get old data.
+    // Invalidate all the group cache because we don't know which groups will be removed.
+    this._cache.removeAllGroups();
+
+    let stmts = [];
+
+    // Get prefs that are about to be removed to notify about their removal.
+    let stmt = this._stmt(`
+      SELECT groups.name AS grp, settings.name AS name
+      FROM prefs
+      JOIN settings ON settings.id = prefs.settingID
+      JOIN groups ON groups.id = prefs.groupID
+      WHERE timestamp >= :since
+    `);
+    stmt.params.since = since;
+    stmts.push(stmt);
+
+    // Do the actual remove.
+    stmt = this._stmt(`
+      DELETE FROM prefs WHERE groupID NOTNULL AND timestamp >= :since
+    `);
+    stmt.params.since = since;
+    stmts.push(stmt);
+
+    // Cleanup no longer used values.
+    stmts = stmts.concat(this._settingsAndGroupsCleanupStmts());
+
+    let prefs = new ContentPrefStore();
+    let isPrivate = context && context.usePrivateBrowsing;
+    this._execStmts(stmts, {
+      onRow: row => {
+        let grp = row.getResultByName("grp");
+        let name = row.getResultByName("name");
+        prefs.set(grp, name, undefined);
+        this._cache.set(grp, name, undefined);
+      },
+      onDone: (reason, ok) => {
+        // This nukes all the groups in _pbStore since we don't have their timestamp
+        // information.
+        if (ok && isPrivate) {
+          for (let [sgroup, sname] of this._pbStore) {
+            if (sgroup) {
+              prefs.set(sgroup, sname, undefined);
+            }
+          }
+          this._pbStore.removeAllGroups();
+        }
+        cbHandleCompletion(callback, reason);
+        if (ok) {
+          for (let [sgroup, sname] of prefs) {
+            this._notifyPrefRemoved(sgroup, sname, isPrivate);
+          }
+        }
+      },
+      onError: nsresult => {
+        cbHandleError(callback, nsresult);
+      },
+    });
+  },
+
+  removeAllDomainsSince: function CPS2_removeAllDomainsSince(
+    since,
+    context,
+    callback
+  ) {
+    this._removeAllDomainsSince(since, context, callback);
+  },
+
+  removeAllDomains: function CPS2_removeAllDomains(context, callback) {
+    this._removeAllDomainsSince(0, context, callback);
+  },
+
+  removeByName: function CPS2_removeByName(name, context, callback) {
+    checkNameArg(name);
+    checkCallbackArg(callback, false);
+
+    // Invalidate the cached values so consumers accessing the cache between now
+    // and when the operation finishes don't get old data.
+    for (let [group, sname] of this._cache) {
+      if (sname == name) {
+        this._cache.remove(group, name);
+      }
+    }
+
+    let stmts = [];
+
+    // First get the matching prefs.  Include null if any of those prefs are
+    // global.
+    let stmt = this._stmt(`
+      SELECT groups.name AS grp
+      FROM prefs
+      JOIN settings ON settings.id = prefs.settingID
+      JOIN groups ON groups.id = prefs.groupID
+      WHERE settings.name = :name
+      UNION
+      SELECT NULL AS grp
+      WHERE EXISTS (
+        SELECT prefs.id
+        FROM prefs
+        JOIN settings ON settings.id = prefs.settingID
+        WHERE settings.name = :name AND prefs.groupID IS NULL
+      )
+    `);
+    stmt.params.name = name;
+    stmts.push(stmt);
+
+    // Delete the target settings.
+    stmt = this._stmt("DELETE FROM settings WHERE name = :name");
+    stmt.params.name = name;
+    stmts.push(stmt);
+
+    // Delete prefs and groups that are no longer used.
+    stmts.push(
+      this._stmt(
+        "DELETE FROM prefs WHERE settingID NOT IN (SELECT id FROM settings)"
+      )
+    );
+    stmts.push(
+      this._stmt(`
+      DELETE FROM groups WHERE id NOT IN (
+        SELECT DISTINCT groupID FROM prefs WHERE groupID NOTNULL
+      )
+    `)
+    );
+
+    let prefs = new ContentPrefStore();
+    let isPrivate = context && context.usePrivateBrowsing;
+
+    this._execStmts(stmts, {
+      onRow: row => {
+        let grp = row.getResultByName("grp");
+        prefs.set(grp, name, undefined);
+        this._cache.set(grp, name, undefined);
+      },
+      onDone: (reason, ok) => {
+        if (ok && isPrivate) {
+          for (let [sgroup, sname] of this._pbStore) {
+            if (sname === name) {
+              prefs.set(sgroup, name, undefined);
+              this._pbStore.remove(sgroup, name);
+            }
+          }
+        }
+        cbHandleCompletion(callback, reason);
+        if (ok) {
+          for (let [sgroup, ,] of prefs) {
+            this._notifyPrefRemoved(sgroup, name, isPrivate);
+          }
+        }
+      },
+      onError: nsresult => {
+        cbHandleError(callback, nsresult);
+      },
+    });
+  },
+
+  /**
+   * Returns the cached mozIStorageAsyncStatement for the given SQL.  If no such
+   * statement is cached, one is created and cached.
+   *
+   * @param sql  The SQL query string.
+   * @return     The cached, possibly new, statement.
+   */
+  _stmt: function CPS2__stmt(sql, cachable = true) {
+    return {
+      sql,
+      cachable,
+      params: {},
+    };
+  },
+
+  /**
+   * Executes some async statements.
+   *
+   * @param stmts      An array of mozIStorageAsyncStatements.
+   * @param callbacks  An object with the following methods:
+   *                   onRow(row) (optional)
+   *                     Called once for each result row.
+   *                     row: A mozIStorageRow.
+   *                   onDone(reason, reasonOK, didGetRow) (required)
+   *                     Called when done.
+   *                     reason: A nsIContentPrefService2.COMPLETE_* value.
+   *                     reasonOK: reason == nsIContentPrefService2.COMPLETE_OK.
+   *                     didGetRow: True if onRow was ever called.
+   *                   onError(nsresult) (optional)
+   *                     Called on error.
+   *                     nsresult: The error code.
+   */
+  _execStmts: async function CPS2__execStmts(stmts, callbacks) {
+    let conn = await this.conn;
+    let rows;
+    let ok = true;
+    try {
+      rows = await executeStatementsInTransaction(conn, stmts);
+    } catch (e) {
+      ok = false;
+      if (callbacks.onError) {
+        try {
+          callbacks.onError(e);
+        } catch (e) {
+          console.error(e);
+        }
+      } else {
+        console.error(e);
+      }
+    }
+
+    if (rows && callbacks.onRow) {
+      for (let row of rows) {
+        try {
+          callbacks.onRow(row);
+        } catch (e) {
+          console.error(e);
+        }
+      }
+    }
+
+    try {
+      callbacks.onDone(
+        ok
+          ? Ci.nsIContentPrefCallback2.COMPLETE_OK
+          : Ci.nsIContentPrefCallback2.COMPLETE_ERROR,
+        ok,
+        rows && !!rows.length
+      );
+    } catch (e) {
+      console.error(e);
+    }
+  },
+
+  /**
+   * Parses the domain (the "group", to use the database's term) from the given
+   * string.
+   *
+   * @param groupStr  Assumed to be either a string or falsey.
+   * @return          If groupStr is a valid URL string, returns the domain of
+   *                  that URL.  If groupStr is some other nonempty string,
+   *                  returns groupStr itself.  Otherwise returns null.
+   *                  The return value is truncated at GROUP_NAME_MAX_LENGTH.
+   */
+  _parseGroup: function CPS2__parseGroup(groupStr) {
+    if (!groupStr) {
+      return null;
+    }
+    try {
+      var groupURI = Services.io.newURI(groupStr);
+      groupStr = HostnameGrouper_group(groupURI);
+    } catch (err) {}
+    return groupStr.substring(
+      0,
+      Ci.nsIContentPrefService2.GROUP_NAME_MAX_LENGTH - 1
+    );
+  },
+
+  _schedule: function CPS2__schedule(fn) {
+    Services.tm.dispatchToMainThread(fn.bind(this));
+  },
+
+  // A hash of arrays of observers, indexed by setting name.
+  _observers: new Map(),
+
+  // An array of generic observers, which observe all settings.
+  _genericObservers: new Set(),
+
+  addObserverForName(aName, aObserver) {
+    let observers;
+    if (aName) {
+      observers = this._observers.get(aName);
+      if (!observers) {
+        observers = new Set();
+        this._observers.set(aName, observers);
+      }
+    } else {
+      observers = this._genericObservers;
+    }
+
+    observers.add(aObserver);
+  },
+
+  removeObserverForName(aName, aObserver) {
+    let observers;
+    if (aName) {
+      observers = this._observers.get(aName);
+      if (!observers) {
+        return;
+      }
+    } else {
+      observers = this._genericObservers;
+    }
+
+    observers.delete(aObserver);
+  },
+
+  /**
+   * Construct a list of observers to notify about a change to some setting,
+   * putting setting-specific observers before before generic ones, so observers
+   * that initialize individual settings (like the page style controller)
+   * execute before observers that display multiple settings and depend on them
+   * being initialized first (like the content prefs sidebar).
+   */
+  _getObservers(aName) {
+    let genericObserverList = Array.from(this._genericObservers);
+    if (aName) {
+      let observersForName = this._observers.get(aName);
+      if (observersForName) {
+        return Array.from(observersForName).concat(genericObserverList);
+      }
+    }
+    return genericObserverList;
+  },
+
+  /**
+   * Notify all observers about the removal of a preference.
+   */
+  _notifyPrefRemoved: function ContentPrefService__notifyPrefRemoved(
+    aGroup,
+    aName,
+    aIsPrivate
+  ) {
+    for (var observer of this._getObservers(aName)) {
+      try {
+        observer.onContentPrefRemoved(aGroup, aName, aIsPrivate);
+      } catch (ex) {
+        console.error(ex);
+      }
+    }
+  },
+
+  /**
+   * Notify all observers about a preference change.
+   */
+  _notifyPrefSet: function ContentPrefService__notifyPrefSet(
+    aGroup,
+    aName,
+    aValue,
+    aIsPrivate
+  ) {
+    for (var observer of this._getObservers(aName)) {
+      try {
+        observer.onContentPrefSet(aGroup, aName, aValue, aIsPrivate);
+      } catch (ex) {
+        console.error(ex);
+      }
+    }
+  },
+
+  extractDomain: function CPS2_extractDomain(str) {
+    return this._parseGroup(str);
+  },
+
+  /**
+   * Tests use this as a backchannel by calling it directly.
+   *
+   * @param subj   This value depends on topic.
+   * @param topic  The backchannel "method" name.
+   * @param data   This value depends on topic.
+   */
+  observe: function CPS2_observe(subj, topic, data) {
+    switch (topic) {
+      case "profile-before-change":
+        this._destroy();
+        break;
+      case "last-pb-context-exited":
+        this._pbStore.removeAll();
+        break;
+      case "test:reset":
+        let fn = subj.QueryInterface(Ci.xpcIJSWeakReference).get();
+        this._reset(fn);
+        break;
+      case "test:db":
+        let obj = subj.QueryInterface(Ci.xpcIJSWeakReference).get();
+        obj.value = this.conn;
+        break;
+    }
+  },
+
+  /**
+   * Removes all state from the service.  Used by tests.
+   *
+   * @param callback  A function that will be called when done.
+   */
+  async _reset(callback) {
+    this._pbStore.removeAll();
+    this._cache.removeAll();
+
+    this._observers = new Map();
+    this._genericObservers = new Set();
+
+    let tables = ["prefs", "groups", "settings"];
+    let stmts = tables.map(t => this._stmt(`DELETE FROM ${t}`));
+    this._execStmts(stmts, {
+      onDone: () => {
+        callback();
+      },
+    });
+  },
+
+  QueryInterface: ChromeUtils.generateQI([
+    "nsIContentPrefService2",
+    "nsIObserver",
+  ]),
+
+  // Database Creation & Access
+
+  _dbVersion: 6,
+
+  _dbSchema: {
+    tables: {
+      groups:
+        "id           INTEGER PRIMARY KEY, \
+                   name         TEXT NOT NULL",
+
+      settings:
+        "id           INTEGER PRIMARY KEY, \
+                   name         TEXT NOT NULL",
+
+      prefs:
+        "id           INTEGER PRIMARY KEY, \
+                   groupID      INTEGER REFERENCES groups(id), \
+                   settingID    INTEGER NOT NULL REFERENCES settings(id), \
+                   value        BLOB, \
+                   timestamp    INTEGER NOT NULL DEFAULT 0", // Storage in seconds, API in ms. 0 for migrated values.
+    },
+    indices: {
+      groups_idx: {
+        table: "groups",
+        columns: ["name"],
+      },
+      settings_idx: {
+        table: "settings",
+        columns: ["name"],
+      },
+      prefs_idx: {
+        table: "prefs",
+        columns: ["timestamp", "groupID", "settingID"],
+      },
+    },
+  },
+
+  _debugLog: false,
+
+  log: function CPS2_log(aMessage) {
+    if (this._debugLog) {
+      Services.console.logStringMessage("ContentPrefService2: " + aMessage);
+    }
+  },
+
+  async _getConnection(aAttemptNum = 0) {
+    if (
+      Services.startup.isInOrBeyondShutdownPhase(
+        Ci.nsIAppStartup.SHUTDOWN_PHASE_APPSHUTDOWN
+      )
+    ) {
+      throw new Error("Can't open content prefs, we're in shutdown.");
+    }
+    let path = PathUtils.join(PathUtils.profileDir, "content-prefs.sqlite");
+    let conn;
+    let resetAndRetry = async e => {
+      if (e.result != Cr.NS_ERROR_FILE_CORRUPTED) {
+        throw e;
+      }
+
+      if (aAttemptNum >= this.MAX_ATTEMPTS) {
+        if (conn) {
+          await conn.close();
+        }
+        this.log("Establishing connection failed too many times. Giving up.");
+        throw e;
+      }
+
+      try {
+        await this._failover(conn, path);
+      } catch (e) {
+        console.error(e);
+        throw e;
+      }
+      return this._getConnection(++aAttemptNum);
+    };
+    try {
+      conn = await lazy.Sqlite.openConnection({
+        path,
+        incrementalVacuum: true,
+        vacuumOnIdle: true,
+      });
+      try {
+        lazy.Sqlite.shutdown.addBlocker(
+          "Closing ContentPrefService2 connection.",
+          () => conn.close()
+        );
+      } catch (ex) {
+        // Uh oh, we failed to add a shutdown blocker. Close the connection
+        // anyway, but make sure that doesn't throw.
+        try {
+          await conn?.close();
+        } catch (ex) {
+          console.error(ex);
+        }
+        return null;
+      }
+    } catch (e) {
+      console.error(e);
+      return resetAndRetry(e);
+    }
+
+    try {
+      await this._dbMaybeInit(conn);
+    } catch (e) {
+      console.error(e);
+      return resetAndRetry(e);
+    }
+
+    // Turn off disk synchronization checking to reduce disk churn and speed up
+    // operations when prefs are changed rapidly (such as when a user repeatedly
+    // changes the value of the browser zoom setting for a site).
+    //
+    // Note: this could cause database corruption if the OS crashes or machine
+    // loses power before the data gets written to disk, but this is considered
+    // a reasonable risk for the not-so-critical data stored in this database.
+    await conn.execute("PRAGMA synchronous = OFF");
+
+    return conn;
+  },
+
+  async _failover(aConn, aPath) {
+    this.log("Cleaning up DB file - close & remove & backup.");
+    if (aConn) {
+      await aConn.close();
+    }
+    let uniquePath = await IOUtils.createUniqueFile(
+      PathUtils.parent(aPath),
+      PathUtils.filename(aPath) + ".corrupt",
+      0o600
+    );
+    await IOUtils.copy(aPath, uniquePath);
+    await IOUtils.remove(aPath);
+    this.log("Completed DB cleanup.");
+  },
+
+  _dbMaybeInit: async function CPS2__dbMaybeInit(aConn) {
+    let version = parseInt(await aConn.getSchemaVersion(), 10);
+    this.log("Schema version: " + version);
+
+    if (version == 0) {
+      await this._dbCreateSchema(aConn);
+    } else if (version != this._dbVersion) {
+      await this._dbMigrate(aConn, version, this._dbVersion);
+    }
+  },
+
+  _createTable: async function CPS2__createTable(aConn, aName) {
+    let tSQL = this._dbSchema.tables[aName];
+    this.log("Creating table " + aName + " with " + tSQL);
+    await aConn.execute(`CREATE TABLE ${aName} (${tSQL})`);
+  },
+
+  _createIndex: async function CPS2__createTable(aConn, aName) {
+    let index = this._dbSchema.indices[aName];
+    let statement =
+      "CREATE INDEX IF NOT EXISTS " +
+      aName +
+      " ON " +
+      index.table +
+      "(" +
+      index.columns.join(", ") +
+      ")";
+    await aConn.execute(statement);
+  },
+
+  _dbCreateSchema: async function CPS2__dbCreateSchema(aConn) {
+    await aConn.executeTransaction(async () => {
+      this.log("Creating DB -- tables");
+      for (let name in this._dbSchema.tables) {
+        await this._createTable(aConn, name);
+      }
+
+      this.log("Creating DB -- indices");
+      for (let name in this._dbSchema.indices) {
+        await this._createIndex(aConn, name);
+      }
+
+      await aConn.setSchemaVersion(this._dbVersion);
+    });
+  },
+
+  _dbMigrate: async function CPS2__dbMigrate(aConn, aOldVersion, aNewVersion) {
+    /**
+     * Migrations should follow the template rules in bug 1074817 comment 3 which are:
+     * 1. Migration should be incremental and non-breaking.
+     * 2. It should be idempotent because one can downgrade an upgrade again.
+     * On downgrade:
+     * 1. Decrement schema version so that upgrade runs the migrations again.
+     */
+    await aConn.executeTransaction(async () => {
+      for (let i = aOldVersion; i < aNewVersion; i++) {
+        let migrationName = "_dbMigrate" + i + "To" + (i + 1);
+        if (typeof this[migrationName] != "function") {
+          throw new Error(
+            "no migrator function from version " +
+              aOldVersion +
+              " to version " +
+              aNewVersion
+          );
+        }
+        await this[migrationName](aConn);
+      }
+      await aConn.setSchemaVersion(aNewVersion);
+    });
+  },
+
+  _dbMigrate1To2: async function CPS2___dbMigrate1To2(aConn) {
+    await aConn.execute("ALTER TABLE groups RENAME TO groupsOld");
+    await this._createTable(aConn, "groups");
+    await aConn.execute(`
+      INSERT INTO groups (id, name)
+      SELECT id, name FROM groupsOld
+    `);
+
+    await aConn.execute("DROP TABLE groupers");
+    await aConn.execute("DROP TABLE groupsOld");
+  },
+
+  _dbMigrate2To3: async function CPS2__dbMigrate2To3(aConn) {
+    for (let name in this._dbSchema.indices) {
+      await this._createIndex(aConn, name);
+    }
+  },
+
+  _dbMigrate3To4: async function CPS2__dbMigrate3To4(aConn) {
+    // Add timestamp column if it does not exist yet. This operation is idempotent.
+    try {
+      await aConn.execute("SELECT timestamp FROM prefs");
+    } catch (e) {
+      await aConn.execute(
+        "ALTER TABLE prefs ADD COLUMN timestamp INTEGER NOT NULL DEFAULT 0"
+      );
+    }
+
+    // To modify prefs_idx drop it and create again.
+    await aConn.execute("DROP INDEX IF EXISTS prefs_idx");
+    for (let name in this._dbSchema.indices) {
+      await this._createIndex(aConn, name);
+    }
+  },
+
+  async _dbMigrate4To5(conn) {
+    // This is a data migration for browser.download.lastDir. While it may not
+    // affect all consumers, it's simpler and safer to do it here than elsewhere.
+    await conn.execute(`
+      DELETE FROM prefs
+      WHERE id IN (
+        SELECT p.id FROM prefs p
+        JOIN groups g ON g.id = p.groupID
+        JOIN settings s ON s.id = p.settingID
+        WHERE s.name = 'browser.download.lastDir'
+          AND (
+          (g.name BETWEEN 'data:' AND 'data:' || X'FFFF') OR
+          (g.name BETWEEN 'file:' AND 'file:' || X'FFFF')
+        )
+      )
+    `);
+    await conn.execute(`
+      DELETE FROM groups WHERE NOT EXISTS (
+        SELECT 1 FROM prefs WHERE groupId = groups.id
+      )
+    `);
+    // Trim group names longer than MAX_GROUP_LENGTH.
+    await conn.execute(
+      `
+      UPDATE groups
+      SET name = substr(name, 0, :maxlen)
+      WHERE LENGTH(name) > :maxlen
+      `,
+      {
+        maxlen: Ci.nsIContentPrefService2.GROUP_NAME_MAX_LENGTH,
+      }
+    );
+  },
+
+  async _dbMigrate5To6(conn) {
+    // This is a data migration for blob: URIs, as we started storing their
+    // origin when possible.
+    // Rather than trying to migrate blob URIs to their origins, that would
+    // require multiple steps for a tiny benefit (they never worked anyway),
+    // just remove them, as they are one-time generated URLs unlikely to be
+    // useful in the future. New inserted blobs will do the right thing.
+    await conn.execute(`
+      DELETE FROM prefs
+      WHERE id IN (
+        SELECT p.id FROM prefs p
+        JOIN groups g ON g.id = p.groupID
+        AND g.name BETWEEN 'blob:' AND 'blob:' || X'FFFF'
+      )
+    `);
+    await conn.execute(`
+      DELETE FROM groups WHERE NOT EXISTS (
+        SELECT 1 FROM prefs WHERE groupId = groups.id
+      )
+    `);
+  },
+};
+
+function checkGroupArg(group) {
+  if (!group || typeof group != "string") {
+    throw invalidArg("domain must be nonempty string.");
+  }
+}
+
+function checkNameArg(name) {
+  if (!name || typeof name != "string") {
+    throw invalidArg("name must be nonempty string.");
+  }
+}
+
+function checkValueArg(value) {
+  if (value === undefined) {
+    throw invalidArg("value must not be undefined.");
+  }
+}
+
+function checkCallbackArg(callback, required) {
+  if (callback && !(callback instanceof Ci.nsIContentPrefCallback2)) {
+    throw invalidArg("callback must be an nsIContentPrefCallback2.");
+  }
+  if (!callback && required) {
+    throw invalidArg("callback must be given.");
+  }
+}
+
+function invalidArg(msg) {
+  return Components.Exception(msg, Cr.NS_ERROR_INVALID_ARG);
+}
+
+// XPCOM Plumbing
diff --git a/toolkit/components/contentprefs/ContentPrefServiceChild.sys.mjs b/toolkit/components/contentprefs/ContentPrefServiceChild.sys.mjs
new file mode 100644
index 0000000000..38d0d3c160
--- /dev/null
+++ b/toolkit/components/contentprefs/ContentPrefServiceChild.sys.mjs
@@ -0,0 +1,185 @@
+/* vim: set ts=2 sw=2 sts=2 et tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import {
+  ContentPref,
+  _methodsCallableFromChild,
+  cbHandleCompletion,
+  cbHandleError,
+  cbHandleResult,
+  safeCallback,
+} from "resource://gre/modules/ContentPrefUtils.sys.mjs";
+
+// We only need one bit of information out of the context.
+function contextArg(context) {
+  return context && context.usePrivateBrowsing
+    ? { usePrivateBrowsing: true }
+    : null;
+}
+
+function NYI() {
+  throw new Error("Do not add any new users of these functions");
+}
+
+function CallbackCaller(callback) {
+  this._callback = callback;
+}
+
+CallbackCaller.prototype = {
+  handleResult(contentPref) {
+    cbHandleResult(
+      this._callback,
+      new ContentPref(contentPref.domain, contentPref.name, contentPref.value)
+    );
+  },
+
+  handleError(result) {
+    cbHandleError(this._callback, result);
+  },
+
+  handleCompletion(reason) {
+    cbHandleCompletion(this._callback, reason);
+  },
+};
+
+export class ContentPrefsChild extends JSProcessActorChild {
+  constructor() {
+    super();
+
+    // Map from pref name -> set of observers
+    this._observers = new Map();
+
+    // Map from random ID string -> CallbackCaller, per request
+    this._requests = new Map();
+  }
+
+  _getRandomId() {
+    return Services.uuid.generateUUID().toString();
+  }
+
+  receiveMessage(msg) {
+    let data = msg.data;
+    let callback;
+    switch (msg.name) {
+      case "ContentPrefs:HandleResult":
+        callback = this._requests.get(data.requestId);
+        callback.handleResult(data.contentPref);
+        break;
+
+      case "ContentPrefs:HandleError":
+        callback = this._requests.get(data.requestId);
+        callback.handleError(data.error);
+        break;
+
+      case "ContentPrefs:HandleCompletion":
+        callback = this._requests.get(data.requestId);
+        this._requests.delete(data.requestId);
+        callback.handleCompletion(data.reason);
+        break;
+
+      case "ContentPrefs:NotifyObservers": {
+        let observerList = this._observers.get(data.name);
+        if (!observerList) {
+          break;
+        }
+
+        for (let observer of observerList) {
+          safeCallback(observer, data.callback, data.args);
+        }
+
+        break;
+      }
+    }
+  }
+
+  callFunction(call, args, callback) {
+    let requestId = this._getRandomId();
+    let data = { call, args, requestId };
+
+    this._requests.set(requestId, new CallbackCaller(callback));
+    this.sendAsyncMessage("ContentPrefs:FunctionCall", data);
+  }
+
+  addObserverForName(name, observer) {
+    let set = this._observers.get(name);
+    if (!set) {
+      set = new Set();
+
+      // This is the first observer for this name. Start listening for changes
+      // to it.
+      this.sendAsyncMessage("ContentPrefs:AddObserverForName", {
+        name,
+      });
+      this._observers.set(name, set);
+    }
+
+    set.add(observer);
+  }
+
+  removeObserverForName(name, observer) {
+    let set = this._observers.get(name);
+    if (!set) {
+      return;
+    }
+
+    set.delete(observer);
+    if (set.size === 0) {
+      // This was the last observer for this name. Stop listening for changes.
+      this.sendAsyncMessage("ContentPrefs:RemoveObserverForName", {
+        name,
+      });
+
+      this._observers.delete(name);
+    }
+  }
+}
+
+export var ContentPrefServiceChild = {
+  QueryInterface: ChromeUtils.generateQI(["nsIContentPrefService2"]),
+
+  addObserverForName: (name, observer) => {
+    ChromeUtils.domProcessChild
+      .getActor("ContentPrefs")
+      .addObserverForName(name, observer);
+  },
+  removeObserverForName: (name, observer) => {
+    ChromeUtils.domProcessChild
+      .getActor("ContentPrefs")
+      .removeObserverForName(name, observer);
+  },
+
+  getCachedByDomainAndName: NYI,
+  getCachedBySubdomainAndName: NYI,
+  getCachedGlobal: NYI,
+  extractDomain: NYI,
+};
+
+function forwardMethodToParent(method, signature, ...args) {
+  // Ignore superfluous arguments
+  args = args.slice(0, signature.length);
+
+  // Process context argument for forwarding
+  let contextIndex = signature.indexOf("context");
+  if (contextIndex > -1) {
+    args[contextIndex] = contextArg(args[contextIndex]);
+  }
+  // Take out the callback argument, if present.
+  let callbackIndex = signature.indexOf("callback");
+  let callback = null;
+  if (callbackIndex > -1 && args.length > callbackIndex) {
+    callback = args.splice(callbackIndex, 1)[0];
+  }
+
+  let actor = ChromeUtils.domProcessChild.getActor("ContentPrefs");
+  actor.callFunction(method, args, callback);
+}
+
+for (let [method, signature] of _methodsCallableFromChild) {
+  ContentPrefServiceChild[method] = forwardMethodToParent.bind(
+    ContentPrefServiceChild,
+    method,
+    signature
+  );
+}
diff --git a/toolkit/components/contentprefs/ContentPrefServiceParent.sys.mjs b/toolkit/components/contentprefs/ContentPrefServiceParent.sys.mjs
new file mode 100644
index 0000000000..66b4a02741
--- /dev/null
+++ b/toolkit/components/contentprefs/ContentPrefServiceParent.sys.mjs
@@ -0,0 +1,160 @@
+/* vim: set ts=2 sw=2 sts=2 et tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  _methodsCallableFromChild: "resource://gre/modules/ContentPrefUtils.sys.mjs",
+});
+
+let loadContext = Cu.createLoadContext();
+let privateLoadContext = Cu.createPrivateLoadContext();
+
+function contextArg(context) {
+  return context && context.usePrivateBrowsing
+    ? privateLoadContext
+    : loadContext;
+}
+
+export class ContentPrefsParent extends JSProcessActorParent {
+  constructor() {
+    super();
+
+    // The names we're using this observer object for, used to keep track
+    // of the number of names we care about as well as for removing this
+    // observer if its associated process goes away.
+    this._prefsToObserve = new Set();
+    this._observer = null;
+  }
+
+  didDestroy() {
+    if (this._observer) {
+      for (let i of this._prefsToObserve) {
+        lazy.cps2.removeObserverForName(i, this._observer);
+      }
+      this._observer = null;
+    }
+  }
+
+  receiveMessage(msg) {
+    switch (msg.name) {
+      case "ContentPrefs:AddObserverForName": {
+        // The child process is responsible for not adding multiple parent
+        // observers for the same name.
+        let actor = this;
+        if (!this._observer) {
+          this._observer = {
+            onContentPrefSet(group, name, value, isPrivate) {
+              actor.onContentPrefSet(group, name, value, isPrivate);
+            },
+            onContentPrefRemoved(group, name, isPrivate) {
+              actor.onContentPrefRemoved(group, name, isPrivate);
+            },
+          };
+        }
+
+        let prefName = msg.data.name;
+        this._prefsToObserve.add(prefName);
+        lazy.cps2.addObserverForName(prefName, this._observer);
+        break;
+      }
+
+      case "ContentPrefs:RemoveObserverForName": {
+        let prefName = msg.data.name;
+        this._prefsToObserve.delete(prefName);
+        if (this._prefsToObserve.size == 0) {
+          lazy.cps2.removeObserverForName(prefName, this._observer);
+          this._observer = null;
+        }
+        break;
+      }
+
+      case "ContentPrefs:FunctionCall":
+        let data = msg.data;
+        let signature;
+
+        if (
+          !lazy._methodsCallableFromChild.some(([method, args]) => {
+            if (method == data.call) {
+              signature = args;
+              return true;
+            }
+            return false;
+          })
+        ) {
+          throw new Error(`Can't call ${data.call} from child!`);
+        }
+
+        let actor = this;
+        let args = data.args;
+
+        return new Promise(resolve => {
+          let listener = {
+            handleResult(pref) {
+              actor.sendAsyncMessage("ContentPrefs:HandleResult", {
+                requestId: data.requestId,
+                contentPref: {
+                  domain: pref.domain,
+                  name: pref.name,
+                  value: pref.value,
+                },
+              });
+            },
+
+            handleError(error) {
+              actor.sendAsyncMessage("ContentPrefs:HandleError", {
+                requestId: data.requestId,
+                error,
+              });
+            },
+            handleCompletion(reason) {
+              actor.sendAsyncMessage("ContentPrefs:HandleCompletion", {
+                requestId: data.requestId,
+                reason,
+              });
+            },
+          };
+          // Push our special listener.
+          args.push(listener);
+
+          // Process context argument for forwarding
+          let contextIndex = signature.indexOf("context");
+          if (contextIndex > -1) {
+            args[contextIndex] = contextArg(args[contextIndex]);
+          }
+
+          // And call the function.
+          lazy.cps2[data.call](...args);
+        });
+    }
+
+    return undefined;
+  }
+
+  onContentPrefSet(group, name, value, isPrivate) {
+    this.sendAsyncMessage("ContentPrefs:NotifyObservers", {
+      name,
+      callback: "onContentPrefSet",
+      args: [group, name, value, isPrivate],
+    });
+  }
+
+  onContentPrefRemoved(group, name, isPrivate) {
+    this.sendAsyncMessage("ContentPrefs:NotifyObservers", {
+      name,
+      callback: "onContentPrefRemoved",
+      args: [group, name, isPrivate],
+    });
+  }
+}
+
+XPCOMUtils.defineLazyServiceGetter(
+  lazy,
+  "cps2",
+  "@mozilla.org/content-pref/service;1",
+  "nsIContentPrefService2"
+);
diff --git a/toolkit/components/contentprefs/ContentPrefStore.sys.mjs b/toolkit/components/contentprefs/ContentPrefStore.sys.mjs
new file mode 100644
index 0000000000..67ba7de317
--- /dev/null
+++ b/toolkit/components/contentprefs/ContentPrefStore.sys.mjs
@@ -0,0 +1,122 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+export function ContentPrefStore() {
+  this._groups = new Map();
+  this._globalNames = new Map();
+}
+
+ContentPrefStore.prototype = {
+  set: function CPS_set(group, name, val) {
+    if (group) {
+      if (!this._groups.has(group)) {
+        this._groups.set(group, new Map());
+      }
+      this._groups.get(group).set(name, val);
+    } else {
+      this._globalNames.set(name, val);
+    }
+  },
+
+  setWithCast: function CPS_setWithCast(group, name, val) {
+    if (typeof val == "boolean") {
+      val = val ? 1 : 0;
+    } else if (val === undefined) {
+      val = null;
+    }
+    this.set(group, name, val);
+  },
+
+  has: function CPS_has(group, name) {
+    if (group) {
+      return this._groups.has(group) && this._groups.get(group).has(name);
+    }
+    return this._globalNames.has(name);
+  },
+
+  get: function CPS_get(group, name) {
+    if (group && this._groups.has(group)) {
+      return this._groups.get(group).get(name);
+    }
+    return this._globalNames.get(name);
+  },
+
+  remove: function CPS_remove(group, name) {
+    if (group) {
+      if (this._groups.has(group)) {
+        this._groups.get(group).delete(name);
+        if (this._groups.get(group).size == 0) {
+          this._groups.delete(group);
+        }
+      }
+    } else {
+      this._globalNames.delete(name);
+    }
+  },
+
+  removeGroup: function CPS_removeGroup(group) {
+    if (group) {
+      this._groups.delete(group);
+    } else {
+      this._globalNames.clear();
+    }
+  },
+
+  removeAllGroups: function CPS_removeAllGroups() {
+    this._groups.clear();
+  },
+
+  removeAll: function CPS_removeAll() {
+    this.removeAllGroups();
+    this._globalNames.clear();
+  },
+
+  groupsMatchIncludingSubdomains: function CPS_groupsMatchIncludingSubdomains(
+    group,
+    group2
+  ) {
+    let idx = group2.indexOf(group);
+    return (
+      idx == group2.length - group.length &&
+      (idx == 0 || group2[idx - 1] == ".")
+    );
+  },
+
+  *[Symbol.iterator]() {
+    for (let [group, names] of this._groups) {
+      for (let [name, val] of names) {
+        yield [group, name, val];
+      }
+    }
+    for (let [name, val] of this._globalNames) {
+      yield [null, name, val];
+    }
+  },
+
+  *match(group, name, includeSubdomains) {
+    for (let sgroup of this.matchGroups(group, includeSubdomains)) {
+      if (this.has(sgroup, name)) {
+        yield [sgroup, this.get(sgroup, name)];
+      }
+    }
+  },
+
+  *matchGroups(group, includeSubdomains) {
+    if (group) {
+      if (includeSubdomains) {
+        for (let [sgroup, ,] of this) {
+          if (sgroup) {
+            if (this.groupsMatchIncludingSubdomains(group, sgroup)) {
+              yield sgroup;
+            }
+          }
+        }
+      } else if (this._groups.has(group)) {
+        yield group;
+      }
+    } else if (this._globalNames.size) {
+      yield null;
+    }
+  },
+};
diff --git a/toolkit/components/contentprefs/ContentPrefUtils.sys.mjs b/toolkit/components/contentprefs/ContentPrefUtils.sys.mjs
new file mode 100644
index 0000000000..0a17913d99
--- /dev/null
+++ b/toolkit/components/contentprefs/ContentPrefUtils.sys.mjs
@@ -0,0 +1,54 @@
+/* vim: set ts=2 sw=2 sts=2 et tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+export function ContentPref(domain, name, value) {
+  this.domain = domain;
+  this.name = name;
+  this.value = value;
+}
+
+ContentPref.prototype = {
+  QueryInterface: ChromeUtils.generateQI(["nsIContentPref"]),
+};
+
+export function cbHandleResult(callback, pref) {
+  safeCallback(callback, "handleResult", [pref]);
+}
+
+export function cbHandleCompletion(callback, reason) {
+  safeCallback(callback, "handleCompletion", [reason]);
+}
+
+export function cbHandleError(callback, nsresult) {
+  safeCallback(callback, "handleError", [nsresult]);
+}
+
+export function safeCallback(callbackObj, methodName, args) {
+  if (!callbackObj || typeof callbackObj[methodName] != "function") {
+    return;
+  }
+  try {
+    callbackObj[methodName].apply(callbackObj, args);
+  } catch (err) {
+    console.error(err);
+  }
+}
+
+export const _methodsCallableFromChild = Object.freeze([
+  ["getByName", ["name", "context", "callback"]],
+  ["getByDomainAndName", ["domain", "name", "context", "callback"]],
+  ["getBySubdomainAndName", ["domain", "name", "context", "callback"]],
+  ["getGlobal", ["name", "context", "callback"]],
+  ["set", ["domain", "name", "value", "context", "callback"]],
+  ["setGlobal", ["name", "value", "context", "callback"]],
+  ["removeByDomainAndName", ["domain", "name", "context", "callback"]],
+  ["removeBySubdomainAndName", ["domain", "name", "context", "callback"]],
+  ["removeGlobal", ["name", "context", "callback"]],
+  ["removeByDomain", ["domain", "context", "callback"]],
+  ["removeBySubdomain", ["domain", "context", "callback"]],
+  ["removeByName", ["name", "context", "callback"]],
+  ["removeAllDomains", ["context", "callback"]],
+  ["removeAllGlobals", ["context", "callback"]],
+]);
diff --git a/toolkit/components/contentprefs/components.conf b/toolkit/components/contentprefs/components.conf
new file mode 100644
index 0000000000..dac48777b5
--- /dev/null
+++ b/toolkit/components/contentprefs/components.conf
@@ -0,0 +1,14 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+Classes = [
+    {
+        'cid': '{e3f772f3-023f-4b32-b074-36cf0fd5d414}',
+        'contract_ids': ['@mozilla.org/content-pref/service;1'],
+        'esModule': 'resource://gre/modules/ContentPrefService2.sys.mjs',
+        'constructor': 'ContentPrefService2',
+    },
+]
diff --git a/toolkit/components/contentprefs/moz.build b/toolkit/components/contentprefs/moz.build
new file mode 100644
index 0000000000..f1caabcf56
--- /dev/null
+++ b/toolkit/components/contentprefs/moz.build
@@ -0,0 +1,26 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+XPCSHELL_TESTS_MANIFESTS += [
+    "tests/unit_cps2/xpcshell.toml",
+]
+
+BROWSER_CHROME_MANIFESTS += ["tests/browser/browser.toml"]
+
+EXTRA_JS_MODULES += [
+    "ContentPrefService2.sys.mjs",
+    "ContentPrefServiceChild.sys.mjs",
+    "ContentPrefServiceParent.sys.mjs",
+    "ContentPrefStore.sys.mjs",
+    "ContentPrefUtils.sys.mjs",
+]
+
+XPCOM_MANIFESTS += [
+    "components.conf",
+]
+
+with Files("**"):
+    BUG_COMPONENT = ("Toolkit", "Preferences")
diff --git a/toolkit/components/contentprefs/tests/browser/browser.toml b/toolkit/components/contentprefs/tests/browser/browser.toml
new file mode 100644
index 0000000000..6901c18348
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/browser/browser.toml
@@ -0,0 +1,3 @@
+[DEFAULT]
+
+["browser_remoteContentPrefs.js"]
diff --git a/toolkit/components/contentprefs/tests/browser/browser_remoteContentPrefs.js b/toolkit/components/contentprefs/tests/browser/browser_remoteContentPrefs.js
new file mode 100644
index 0000000000..00c845e488
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/browser/browser_remoteContentPrefs.js
@@ -0,0 +1,242 @@
+"use strict";
+
+const childFrameURL = Services.io.newURI(
+  "data:text/html,<!DOCTYPE HTML><html><body></body></html>"
+);
+
+async function runTestsForFrame(browser, isPrivate) {
+  let loadContext = Cu.createLoadContext();
+  let privateLoadContext = Cu.createPrivateLoadContext();
+
+  await SpecialPowers.spawn(browser, [], async () => {
+    var cps = Cc["@mozilla.org/content-pref/service;1"].getService(
+      Ci.nsIContentPrefService2
+    );
+    Assert.ok(cps !== null, "got the content pref service");
+
+    await new Promise(resolve => {
+      cps.setGlobal("testing", 42, null, {
+        handleCompletion(reason) {
+          Assert.equal(reason, 0, "set a pref?");
+          resolve();
+        },
+      });
+    });
+
+    let numResults = 0;
+    await new Promise(resolve => {
+      cps.getGlobal("testing", null, {
+        handleResult(pref) {
+          numResults++;
+          Assert.equal(pref.name, "testing", "pref has the right name");
+          Assert.equal(pref.value, 42, "pref has the right value");
+        },
+
+        handleCompletion(reason) {
+          Assert.equal(reason, 0, "get a pref?");
+          Assert.equal(numResults, 1, "got the right number of prefs");
+          resolve();
+        },
+      });
+    });
+  });
+
+  await SpecialPowers.spawn(browser, [isPrivate], async isFramePrivate => {
+    var cps = Cc["@mozilla.org/content-pref/service;1"].getService(
+      Ci.nsIContentPrefService2
+    );
+
+    if (!content._result) {
+      content._result = [];
+    }
+
+    let observer;
+    cps.addObserverForName(
+      "testName",
+      (observer = {
+        onContentPrefSet(group, name, value, isPrivate) {
+          Assert.equal(group, null, "group should be null");
+          Assert.equal(name, "testName", "should only see testName");
+          Assert.equal(value, 42, "value should be correct");
+          Assert.equal(isPrivate, isFramePrivate, "privacy should match");
+
+          content._result.push("set");
+        },
+
+        onContentPrefRemoved(group, name, isPrivate) {
+          Assert.equal(group, null, "group should be null");
+          Assert.equal(name, "testName", "name should match");
+          Assert.equal(isPrivate, isFramePrivate, "privacy should match");
+
+          content._result.push("removed");
+        },
+      })
+    );
+    content._observer = observer;
+  });
+
+  for (let expectedResponse of ["set", "removed"]) {
+    var cps = Cc["@mozilla.org/content-pref/service;1"].getService(
+      Ci.nsIContentPrefService2
+    );
+
+    if (expectedResponse == "set") {
+      cps.setGlobal(
+        "testName",
+        42,
+        isPrivate ? privateLoadContext : loadContext
+      );
+    } else {
+      cps.removeGlobal(
+        "testName",
+        isPrivate ? privateLoadContext : loadContext
+      );
+    }
+
+    let response = await SpecialPowers.spawn(
+      browser,
+      [expectedResponse],
+      async expected => {
+        var cps = Cc["@mozilla.org/content-pref/service;1"].getService(
+          Ci.nsIContentPrefService2
+        );
+        await ContentTaskUtils.waitForCondition(
+          () => content._result.length == 1,
+          "expecting one notification"
+        );
+
+        if (expected == "removed") {
+          cps.removeObserverForName("testName", content._observer);
+        }
+
+        Assert.equal(
+          content._result.length,
+          1,
+          "correct number of notifications"
+        );
+        let result = content._result[0];
+        content._result = [];
+        return result;
+      }
+    );
+
+    is(response, expectedResponse, "got correct observer notification");
+  }
+
+  await SpecialPowers.spawn(browser, [], async () => {
+    var cps = Cc["@mozilla.org/content-pref/service;1"].getService(
+      Ci.nsIContentPrefService2
+    );
+
+    await new Promise(resolve => {
+      cps.setGlobal("testName", 42, null, {
+        handleCompletion(reason) {
+          Assert.equal(reason, 0, "set a pref");
+          cps.set("http://mochi.test", "testpref", "str", null, {
+            /* eslint no-shadow: 0 */
+            handleCompletion(reason) {
+              Assert.equal(reason, 0, "set a pref");
+              resolve();
+            },
+          });
+        },
+      });
+    });
+
+    await new Promise(resolve => {
+      cps.removeByDomain("http://mochi.test", null, {
+        handleCompletion(reason) {
+          Assert.equal(reason, 0, "remove succeeded");
+          cps.getByDomainAndName("http://mochi.test", "testpref", null, {
+            handleResult() {
+              throw new Error("got removed pref in test3");
+            },
+            handleCompletion() {
+              resolve();
+            },
+            handleError(rv) {
+              throw new Error(`got a pref error ${rv}`);
+            },
+          });
+        },
+      });
+    });
+  });
+
+  await SpecialPowers.spawn(browser, [], async () => {
+    var cps = Cc["@mozilla.org/content-pref/service;1"].getService(
+      Ci.nsIContentPrefService2
+    );
+
+    let event = await new Promise((resolve, reject) => {
+      let prefObserver = {
+        onContentPrefSet(group, name, value, isPrivate) {
+          resolve({ group, name, value, isPrivate });
+        },
+        onContentPrefRemoved(group, name, isPrivate) {
+          reject("got unexpected notification");
+        },
+      };
+
+      cps.addObserverForName("test", prefObserver);
+
+      let privateLoadContext = Cu.createPrivateLoadContext();
+      cps.set("http://mochi.test", "test", 42, privateLoadContext);
+
+      cps.addObserverForName("test", prefObserver);
+    });
+
+    Assert.equal(event.name, "test", "got the right event");
+    Assert.equal(event.isPrivate, true, "the event was for an isPrivate pref");
+  });
+
+  await SpecialPowers.spawn(browser, [], async () => {
+    var cps = Cc["@mozilla.org/content-pref/service;1"].getService(
+      Ci.nsIContentPrefService2
+    );
+
+    let results = [];
+    await new Promise(resolve => {
+      cps.getByDomainAndName("http://mochi.test", "test", null, {
+        handleResult(pref) {
+          info("received handleResult");
+          results.push(pref);
+        },
+        handleCompletion(reason) {
+          resolve();
+        },
+        handleError(rv) {
+          ok(false, `failed to get pref ${rv}`);
+          throw new Error("got unexpected error");
+        },
+      });
+    });
+
+    Assert.equal(results.length, 0, "should not have seen the pb pref");
+  });
+}
+
+async function runTest(isPrivate) {
+  /* globals Services */
+  info("testing with isPrivate=" + isPrivate);
+
+  let newWindow = await BrowserTestUtils.openNewBrowserWindow({
+    private: isPrivate,
+  });
+
+  const system = Services.scriptSecurityManager.getSystemPrincipal();
+
+  let browser = newWindow.gBrowser.selectedBrowser;
+  let loadedPromise = BrowserTestUtils.browserLoaded(browser);
+  browser.loadURI(childFrameURL, { triggeringPrincipal: system });
+  await loadedPromise;
+
+  await runTestsForFrame(browser, isPrivate);
+
+  newWindow.close();
+}
+
+add_task(async function () {
+  await runTest(false);
+  await runTest(true);
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/AsyncRunner.sys.mjs b/toolkit/components/contentprefs/tests/unit_cps2/AsyncRunner.sys.mjs
new file mode 100644
index 0000000000..3fab7c981f
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/AsyncRunner.sys.mjs
@@ -0,0 +1,59 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+export function AsyncRunner(callbacks) {
+  this._callbacks = callbacks;
+  this._iteratorQueue = [];
+
+  // This catches errors reported to the console, e.g., via Cu.reportError.
+  Services.console.registerListener(this);
+}
+
+AsyncRunner.prototype = {
+  appendIterator: function AR_appendIterator(iter) {
+    this._iteratorQueue.push(iter);
+  },
+
+  next: function AR_next(arg) {
+    if (!this._iteratorQueue.length) {
+      this.destroy();
+      this._callbacks.done();
+      return;
+    }
+
+    try {
+      var { done, value } = this._iteratorQueue[0].next(arg);
+      if (done) {
+        this._iteratorQueue.shift();
+        this.next();
+        return;
+      }
+    } catch (err) {
+      this._callbacks.error(err);
+    }
+
+    // val is truthy => call next
+    // val is an iterator => prepend it to the queue and start on it
+    if (value) {
+      if (typeof value != "boolean") {
+        this._iteratorQueue.unshift(value);
+      }
+      this.next();
+    }
+  },
+
+  destroy: function AR_destroy() {
+    Services.console.unregisterListener(this);
+    this.destroy = function AR_alreadyDestroyed() {};
+  },
+
+  observe: function AR_consoleServiceListener(msg) {
+    if (
+      msg instanceof Ci.nsIScriptError &&
+      !(msg.flags & Ci.nsIScriptError.warningFlag)
+    ) {
+      this._callbacks.consoleError(msg);
+    }
+  },
+};
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/head.js b/toolkit/components/contentprefs/tests/unit_cps2/head.js
new file mode 100644
index 0000000000..c500d2bf01
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/head.js
@@ -0,0 +1,360 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+let loadContext = Cu.createLoadContext();
+let privateLoadContext = Cu.createPrivateLoadContext();
+
+const CURRENT_DB_VERSION = 6;
+
+// There has to be a profile directory before the CPS service is gotten.
+do_get_profile();
+let cps = Cc["@mozilla.org/content-pref/service;1"].getService(
+  Ci.nsIContentPrefService2
+);
+
+function makeCallback(resolve, callbacks, success = null) {
+  callbacks = callbacks || {};
+  if (!callbacks.handleError) {
+    callbacks.handleError = function (error) {
+      do_throw("handleError call was not expected, error: " + error);
+    };
+  }
+  if (!callbacks.handleResult) {
+    callbacks.handleResult = function () {
+      do_throw("handleResult call was not expected");
+    };
+  }
+  if (!callbacks.handleCompletion) {
+    callbacks.handleCompletion = function (reason) {
+      equal(reason, Ci.nsIContentPrefCallback2.COMPLETE_OK);
+      if (success) {
+        success();
+      } else {
+        resolve();
+      }
+    };
+  }
+  return callbacks;
+}
+
+async function do_check_throws(fn) {
+  let threw = false;
+  try {
+    await fn();
+  } catch (err) {
+    threw = true;
+  }
+  ok(threw);
+}
+
+function sendMessage(msg, callback) {
+  let obj = callback || {};
+  let ref = Cu.getWeakReference(obj);
+  cps.QueryInterface(Ci.nsIObserver).observe(ref, "test:" + msg, null);
+  return "value" in obj ? obj.value : undefined;
+}
+
+function reset() {
+  return new Promise(resolve => {
+    sendMessage("reset", resolve);
+  });
+}
+
+function setWithDate(group, name, val, timestamp, context) {
+  return new Promise(resolve => {
+    async function updateDate() {
+      let conn = await sendMessage("db");
+      await conn.execute(
+        `
+        UPDATE prefs SET timestamp = :timestamp
+        WHERE
+          settingID = (SELECT id FROM settings WHERE name = :name)
+          AND groupID = (SELECT id FROM groups WHERE name = :group)
+      `,
+        { name, group, timestamp: timestamp / 1000 }
+      );
+
+      resolve();
+    }
+
+    cps.set(group, name, val, context, makeCallback(null, null, updateDate));
+  });
+}
+
+async function getDate(group, name, context) {
+  let conn = await sendMessage("db");
+  let [result] = await conn.execute(
+    `
+      SELECT timestamp FROM prefs
+      WHERE
+        settingID = (SELECT id FROM settings WHERE name = :name)
+        AND groupID = (SELECT id FROM groups WHERE name = :group)
+  `,
+    { name, group }
+  );
+
+  return result.getResultByName("timestamp") * 1000;
+}
+
+function set(group, name, val, context) {
+  return new Promise(resolve => {
+    cps.set(group, name, val, context, makeCallback(resolve));
+  });
+}
+
+function setGlobal(name, val, context) {
+  return new Promise(resolve => {
+    cps.setGlobal(name, val, context, makeCallback(resolve));
+  });
+}
+
+function prefOK(actual, expected, strict) {
+  ok(actual instanceof Ci.nsIContentPref);
+  equal(actual.domain, expected.domain);
+  equal(actual.name, expected.name);
+  if (strict) {
+    strictEqual(actual.value, expected.value);
+  } else {
+    equal(actual.value, expected.value);
+  }
+}
+
+async function getOK(args, expectedVal, expectedGroup, strict) {
+  if (args.length == 2) {
+    args.push(undefined);
+  }
+  let expectedPrefs =
+    expectedVal === undefined
+      ? []
+      : [
+          {
+            domain: expectedGroup || args[0],
+            name: args[1],
+            value: expectedVal,
+          },
+        ];
+  await getOKEx("getByDomainAndName", args, expectedPrefs, strict);
+}
+
+async function getSubdomainsOK(args, expectedGroupValPairs) {
+  if (args.length == 2) {
+    args.push(undefined);
+  }
+  let expectedPrefs = expectedGroupValPairs.map(function ([group, val]) {
+    return { domain: group, name: args[1], value: val };
+  });
+  await getOKEx("getBySubdomainAndName", args, expectedPrefs);
+}
+
+async function getGlobalOK(args, expectedVal) {
+  if (args.length == 1) {
+    args.push(undefined);
+  }
+  let expectedPrefs =
+    expectedVal === undefined
+      ? []
+      : [{ domain: null, name: args[0], value: expectedVal }];
+  await getOKEx("getGlobal", args, expectedPrefs);
+}
+
+async function getOKEx(methodName, args, expectedPrefs, strict, context) {
+  let actualPrefs = [];
+  await new Promise(resolve => {
+    args.push(
+      makeCallback(resolve, {
+        handleResult: pref => actualPrefs.push(pref),
+      })
+    );
+    cps[methodName].apply(cps, args);
+  });
+  arraysOfArraysOK([actualPrefs], [expectedPrefs], function (actual, expected) {
+    prefOK(actual, expected, strict);
+  });
+}
+
+function getCachedOK(
+  args,
+  expectedIsCached,
+  expectedVal,
+  expectedGroup,
+  strict
+) {
+  if (args.length == 2) {
+    args.push(undefined);
+  }
+  let expectedPref = !expectedIsCached
+    ? null
+    : {
+        domain: expectedGroup || args[0],
+        name: args[1],
+        value: expectedVal,
+      };
+  getCachedOKEx("getCachedByDomainAndName", args, expectedPref, strict);
+}
+
+function getCachedSubdomainsOK(args, expectedGroupValPairs) {
+  if (args.length == 2) {
+    args.push(undefined);
+  }
+  let actualPrefs = cps.getCachedBySubdomainAndName.apply(cps, args);
+  actualPrefs = actualPrefs.sort(function (a, b) {
+    return a.domain.localeCompare(b.domain);
+  });
+  let expectedPrefs = expectedGroupValPairs.map(function ([group, val]) {
+    return { domain: group, name: args[1], value: val };
+  });
+  arraysOfArraysOK([actualPrefs], [expectedPrefs], prefOK);
+}
+
+function getCachedGlobalOK(args, expectedIsCached, expectedVal) {
+  if (args.length == 1) {
+    args.push(undefined);
+  }
+  let expectedPref = !expectedIsCached
+    ? null
+    : {
+        domain: null,
+        name: args[0],
+        value: expectedVal,
+      };
+  getCachedOKEx("getCachedGlobal", args, expectedPref);
+}
+
+function getCachedOKEx(methodName, args, expectedPref, strict) {
+  let actualPref = cps[methodName].apply(cps, args);
+  if (expectedPref) {
+    prefOK(actualPref, expectedPref, strict);
+  } else {
+    strictEqual(actualPref, null);
+  }
+}
+
+function arraysOK(actual, expected, cmp) {
+  if (actual.length != expected.length) {
+    do_throw(
+      "Length is not equal: " +
+        JSON.stringify(actual) +
+        "==" +
+        JSON.stringify(expected)
+    );
+  } else {
+    actual.forEach(function (actualElt, j) {
+      let expectedElt = expected[j];
+      cmp(actualElt, expectedElt);
+    });
+  }
+}
+
+function arraysOfArraysOK(actual, expected, cmp) {
+  cmp = cmp || equal;
+  arraysOK(actual, expected, function (act, exp) {
+    arraysOK(act, exp, cmp);
+  });
+}
+
+async function dbOK(expectedRows) {
+  let conn = await sendMessage("db");
+  let stmt = `
+    SELECT groups.name AS grp, settings.name AS name, prefs.value AS value
+    FROM prefs
+    LEFT JOIN groups ON groups.id = prefs.groupID
+    LEFT JOIN settings ON settings.id = prefs.settingID
+    UNION
+
+    /*
+      These second two SELECTs get the rows of the groups and settings tables
+      that aren't referenced by the prefs table.  Neither should return any
+      rows if the component is working properly.
+    */
+    SELECT groups.name AS grp, NULL AS name, NULL AS value
+    FROM groups
+    WHERE id NOT IN (
+      SELECT DISTINCT groupID
+      FROM prefs
+      WHERE groupID NOTNULL
+    )
+    UNION
+    SELECT NULL AS grp, settings.name AS name, NULL AS value
+    FROM settings
+    WHERE id NOT IN (
+      SELECT DISTINCT settingID
+      FROM prefs
+      WHERE settingID NOTNULL
+    )
+
+    ORDER BY value ASC, grp ASC, name ASC
+  `;
+
+  let cols = ["grp", "name", "value"];
+
+  let actualRows = (await conn.execute(stmt)).map(row =>
+    cols.map(c => row.getResultByName(c))
+  );
+  arraysOfArraysOK(actualRows, expectedRows);
+}
+
+function on(event, names, dontRemove) {
+  return onEx(event, names, dontRemove).promise;
+}
+
+function onEx(event, names, dontRemove) {
+  let args = {
+    reset() {
+      for (let prop in this) {
+        if (Array.isArray(this[prop])) {
+          this[prop].splice(0, this[prop].length);
+        }
+      }
+    },
+  };
+
+  let observers = {};
+  let deferred = null;
+  let triggered = false;
+
+  names.forEach(function (name) {
+    let obs = {};
+    ["onContentPrefSet", "onContentPrefRemoved"].forEach(function (meth) {
+      obs[meth] = () => do_throw(meth + " should not be called for " + name);
+    });
+    obs["onContentPref" + event] = function () {
+      args[name].push(Array.from(arguments));
+
+      if (!triggered) {
+        triggered = true;
+        executeSoon(function () {
+          if (!dontRemove) {
+            names.forEach(n => cps.removeObserverForName(n, observers[n]));
+          }
+          deferred.resolve(args);
+        });
+      }
+    };
+    observers[name] = obs;
+    args[name] = [];
+    args[name].observer = obs;
+    cps.addObserverForName(name, obs);
+  });
+
+  return {
+    observers,
+    promise: new Promise(resolve => {
+      deferred = { resolve };
+    }),
+  };
+}
+
+async function schemaVersionIs(expectedVersion) {
+  let db = await sendMessage("db");
+  equal(await db.getSchemaVersion(), expectedVersion);
+}
+
+function wait() {
+  return new Promise(resolve => executeSoon(resolve));
+}
+
+function observerArgsOK(actualArgs, expectedArgs) {
+  notEqual(actualArgs, undefined);
+  arraysOfArraysOK(actualArgs, expectedArgs);
+}
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_extractDomain.js b/toolkit/components/contentprefs/tests/unit_cps2/test_extractDomain.js
new file mode 100644
index 0000000000..2e3fe5675a
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_extractDomain.js
@@ -0,0 +1,26 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+function run_test() {
+  let tests = {
+    "blob:": "blob:",
+    "blob:https://chat.mozilla.org/35d6a992-6e18-4957-8216-070c53b9bc83":
+      "chat.mozilla.org",
+    "blob:resource://pdf.js/ed645567-3eea-4ff1-94fd-efb04812afe0":
+      "resource://pdf.js",
+    "http://example.com": "example.com",
+    "http://example.com/": "example.com",
+    "http://example.com/foo/bar/baz": "example.com",
+    "http://subdomain.example.com/foo/bar/baz": "subdomain.example.com",
+    "http://qix.quux.example.com/foo/bar/baz": "qix.quux.example.com",
+    "file:///home/foo/bar": "file:///home/foo/bar",
+    "not a url": "not a url",
+  };
+  let cps = Cc["@mozilla.org/content-pref/service;1"].getService(
+    Ci.nsIContentPrefService2
+  );
+  for (let url in tests) {
+    Assert.equal(cps.extractDomain(url), tests[url]);
+  }
+}
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_getCached.js b/toolkit/components/contentprefs/tests/unit_cps2/test_getCached.js
new file mode 100644
index 0000000000..d8a70a545a
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_getCached.js
@@ -0,0 +1,97 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+add_task(async function resetBeforeTests() {
+  await reset();
+});
+
+add_task(async function nonexistent() {
+  getCachedOK(["a.com", "foo"], false, undefined);
+  getCachedGlobalOK(["foo"], false, undefined);
+  await reset();
+});
+
+add_task(async function isomorphicDomains() {
+  await set("a.com", "foo", 1);
+  getCachedOK(["a.com", "foo"], true, 1);
+  getCachedOK(["http://a.com/huh", "foo"], true, 1, "a.com");
+  await reset();
+});
+
+add_task(async function names() {
+  await set("a.com", "foo", 1);
+  getCachedOK(["a.com", "foo"], true, 1);
+
+  await set("a.com", "bar", 2);
+  getCachedOK(["a.com", "foo"], true, 1);
+  getCachedOK(["a.com", "bar"], true, 2);
+
+  await setGlobal("foo", 3);
+  getCachedOK(["a.com", "foo"], true, 1);
+  getCachedOK(["a.com", "bar"], true, 2);
+  getCachedGlobalOK(["foo"], true, 3);
+
+  await setGlobal("bar", 4);
+  getCachedOK(["a.com", "foo"], true, 1);
+  getCachedOK(["a.com", "bar"], true, 2);
+  getCachedGlobalOK(["foo"], true, 3);
+  getCachedGlobalOK(["bar"], true, 4);
+  await reset();
+});
+
+add_task(async function subdomains() {
+  await set("a.com", "foo", 1);
+  await set("b.a.com", "foo", 2);
+  getCachedOK(["a.com", "foo"], true, 1);
+  getCachedOK(["b.a.com", "foo"], true, 2);
+  await reset();
+});
+
+add_task(async function privateBrowsing() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await set("b.com", "foo", 5);
+
+  let context = privateLoadContext;
+  await set("a.com", "foo", 6, context);
+  await setGlobal("foo", 7, context);
+  getCachedOK(["a.com", "foo", context], true, 6);
+  getCachedOK(["a.com", "bar", context], true, 2);
+  getCachedGlobalOK(["foo", context], true, 7);
+  getCachedGlobalOK(["bar", context], true, 4);
+  getCachedOK(["b.com", "foo", context], true, 5);
+
+  getCachedOK(["a.com", "foo"], true, 1);
+  getCachedOK(["a.com", "bar"], true, 2);
+  getCachedGlobalOK(["foo"], true, 3);
+  getCachedGlobalOK(["bar"], true, 4);
+  getCachedOK(["b.com", "foo"], true, 5);
+  await reset();
+});
+
+add_task(async function erroneous() {
+  do_check_throws(() => cps.getCachedByDomainAndName(null, "foo", null));
+  do_check_throws(() => cps.getCachedByDomainAndName("", "foo", null));
+  do_check_throws(() => cps.getCachedByDomainAndName("a.com", "", null));
+  do_check_throws(() => cps.getCachedByDomainAndName("a.com", null, null));
+  do_check_throws(() => cps.getCachedGlobal("", null));
+  do_check_throws(() => cps.getCachedGlobal(null, null));
+  await reset();
+});
+
+add_task(async function casts() {
+  // SQLite casts booleans to integers.  This makes sure the values stored in
+  // the cache are the same as the casted values in the database.
+
+  await set("a.com", "foo", false);
+  await getOK(["a.com", "foo"], 0, "a.com", true);
+  getCachedOK(["a.com", "foo"], true, 0, "a.com", true);
+
+  await set("a.com", "bar", true);
+  await getOK(["a.com", "bar"], 1, "a.com", true);
+  getCachedOK(["a.com", "bar"], true, 1, "a.com", true);
+  await reset();
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_getCachedSubdomains.js b/toolkit/components/contentprefs/tests/unit_cps2/test_getCachedSubdomains.js
new file mode 100644
index 0000000000..ed15e6fb0e
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_getCachedSubdomains.js
@@ -0,0 +1,259 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+add_task(async function resetBeforeTests() {
+  await reset();
+});
+
+add_task(async function nonexistent() {
+  getCachedSubdomainsOK(["a.com", "foo"], []);
+  await reset();
+});
+
+add_task(async function isomorphicDomains() {
+  await set("a.com", "foo", 1);
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", 1]]);
+  getCachedSubdomainsOK(["http://a.com/huh", "foo"], [["a.com", 1]]);
+  await reset();
+});
+
+add_task(async function names() {
+  await set("a.com", "foo", 1);
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", 1]]);
+
+  await set("a.com", "bar", 2);
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", 1]]);
+  getCachedSubdomainsOK(["a.com", "bar"], [["a.com", 2]]);
+
+  await setGlobal("foo", 3);
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", 1]]);
+  getCachedSubdomainsOK(["a.com", "bar"], [["a.com", 2]]);
+  getCachedGlobalOK(["foo"], true, 3);
+
+  await setGlobal("bar", 4);
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", 1]]);
+  getCachedSubdomainsOK(["a.com", "bar"], [["a.com", 2]]);
+  getCachedGlobalOK(["foo"], true, 3);
+  getCachedGlobalOK(["bar"], true, 4);
+  await reset();
+});
+
+add_task(async function subdomains() {
+  await set("a.com", "foo", 1);
+  await set("b.a.com", "foo", 2);
+  getCachedSubdomainsOK(
+    ["a.com", "foo"],
+    [
+      ["a.com", 1],
+      ["b.a.com", 2],
+    ]
+  );
+  getCachedSubdomainsOK(["b.a.com", "foo"], [["b.a.com", 2]]);
+  await reset();
+});
+
+add_task(async function populateViaGet() {
+  await new Promise(resolve =>
+    cps.getByDomainAndName("a.com", "foo", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", undefined]]);
+
+  await new Promise(resolve =>
+    cps.getGlobal("foo", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", undefined]]);
+  getCachedGlobalOK(["foo"], true, undefined);
+  await reset();
+});
+
+add_task(async function populateViaGetSubdomains() {
+  await new Promise(resolve =>
+    cps.getBySubdomainAndName("a.com", "foo", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", undefined]]);
+  await reset();
+});
+
+add_task(async function populateViaRemove() {
+  await new Promise(resolve =>
+    cps.removeByDomainAndName("a.com", "foo", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", undefined]]);
+
+  await new Promise(resolve =>
+    cps.removeBySubdomainAndName("b.com", "foo", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", undefined]]);
+  getCachedSubdomainsOK(["b.com", "foo"], [["b.com", undefined]]);
+
+  await new Promise(resolve =>
+    cps.removeGlobal("foo", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", undefined]]);
+  getCachedSubdomainsOK(["b.com", "foo"], [["b.com", undefined]]);
+  getCachedGlobalOK(["foo"], true, undefined);
+
+  await set("a.com", "foo", 1);
+  await new Promise(resolve =>
+    cps.removeByDomainAndName("a.com", "foo", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", undefined]]);
+  getCachedSubdomainsOK(["b.com", "foo"], [["b.com", undefined]]);
+  getCachedGlobalOK(["foo"], true, undefined);
+
+  await set("a.com", "foo", 2);
+  await set("b.a.com", "foo", 3);
+  await new Promise(resolve =>
+    cps.removeBySubdomainAndName("a.com", "foo", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(
+    ["a.com", "foo"],
+    [
+      ["a.com", undefined],
+      ["b.a.com", undefined],
+    ]
+  );
+  getCachedSubdomainsOK(["b.com", "foo"], [["b.com", undefined]]);
+  getCachedGlobalOK(["foo"], true, undefined);
+  getCachedSubdomainsOK(["b.a.com", "foo"], [["b.a.com", undefined]]);
+
+  await setGlobal("foo", 4);
+  await new Promise(resolve =>
+    cps.removeGlobal("foo", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(
+    ["a.com", "foo"],
+    [
+      ["a.com", undefined],
+      ["b.a.com", undefined],
+    ]
+  );
+  getCachedSubdomainsOK(["b.com", "foo"], [["b.com", undefined]]);
+  getCachedGlobalOK(["foo"], true, undefined);
+  getCachedSubdomainsOK(["b.a.com", "foo"], [["b.a.com", undefined]]);
+  await reset();
+});
+
+add_task(async function populateViaRemoveByDomain() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await set("b.a.com", "foo", 3);
+  await set("b.a.com", "bar", 4);
+  await new Promise(resolve =>
+    cps.removeByDomain("a.com", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(
+    ["a.com", "foo"],
+    [
+      ["a.com", undefined],
+      ["b.a.com", 3],
+    ]
+  );
+  getCachedSubdomainsOK(
+    ["a.com", "bar"],
+    [
+      ["a.com", undefined],
+      ["b.a.com", 4],
+    ]
+  );
+
+  await set("a.com", "foo", 5);
+  await set("a.com", "bar", 6);
+  await new Promise(resolve =>
+    cps.removeBySubdomain("a.com", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(
+    ["a.com", "foo"],
+    [
+      ["a.com", undefined],
+      ["b.a.com", undefined],
+    ]
+  );
+  getCachedSubdomainsOK(
+    ["a.com", "bar"],
+    [
+      ["a.com", undefined],
+      ["b.a.com", undefined],
+    ]
+  );
+
+  await setGlobal("foo", 7);
+  await setGlobal("bar", 8);
+  await new Promise(resolve =>
+    cps.removeAllGlobals(null, makeCallback(resolve))
+  );
+  getCachedGlobalOK(["foo"], true, undefined);
+  getCachedGlobalOK(["bar"], true, undefined);
+  await reset();
+});
+
+add_task(async function populateViaRemoveAllDomains() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await set("b.com", "foo", 3);
+  await set("b.com", "bar", 4);
+  await new Promise(resolve =>
+    cps.removeAllDomains(null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", undefined]]);
+  getCachedSubdomainsOK(["a.com", "bar"], [["a.com", undefined]]);
+  getCachedSubdomainsOK(["b.com", "foo"], [["b.com", undefined]]);
+  getCachedSubdomainsOK(["b.com", "bar"], [["b.com", undefined]]);
+  await reset();
+});
+
+add_task(async function populateViaRemoveByName() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await new Promise(resolve =>
+    cps.removeByName("foo", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", undefined]]);
+  getCachedSubdomainsOK(["a.com", "bar"], [["a.com", 2]]);
+  getCachedGlobalOK(["foo"], true, undefined);
+  getCachedGlobalOK(["bar"], true, 4);
+
+  await new Promise(resolve =>
+    cps.removeByName("bar", null, makeCallback(resolve))
+  );
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", undefined]]);
+  getCachedSubdomainsOK(["a.com", "bar"], [["a.com", undefined]]);
+  getCachedGlobalOK(["foo"], true, undefined);
+  getCachedGlobalOK(["bar"], true, undefined);
+  await reset();
+});
+
+add_task(async function privateBrowsing() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await set("b.com", "foo", 5);
+
+  let context = privateLoadContext;
+  await set("a.com", "foo", 6, context);
+  await setGlobal("foo", 7, context);
+  getCachedSubdomainsOK(["a.com", "foo", context], [["a.com", 6]]);
+  getCachedSubdomainsOK(["a.com", "bar", context], [["a.com", 2]]);
+  getCachedGlobalOK(["foo", context], true, 7);
+  getCachedGlobalOK(["bar", context], true, 4);
+  getCachedSubdomainsOK(["b.com", "foo", context], [["b.com", 5]]);
+
+  getCachedSubdomainsOK(["a.com", "foo"], [["a.com", 1]]);
+  getCachedSubdomainsOK(["a.com", "bar"], [["a.com", 2]]);
+  getCachedGlobalOK(["foo"], true, 3);
+  getCachedGlobalOK(["bar"], true, 4);
+  getCachedSubdomainsOK(["b.com", "foo"], [["b.com", 5]]);
+  await reset();
+});
+
+add_task(async function erroneous() {
+  do_check_throws(() => cps.getCachedBySubdomainAndName(null, "foo", null));
+  do_check_throws(() => cps.getCachedBySubdomainAndName("", "foo", null));
+  do_check_throws(() => cps.getCachedBySubdomainAndName("a.com", "", null));
+  do_check_throws(() => cps.getCachedBySubdomainAndName("a.com", null, null));
+  await reset();
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_getSubdomains.js b/toolkit/components/contentprefs/tests/unit_cps2/test_getSubdomains.js
new file mode 100644
index 0000000000..7015174d53
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_getSubdomains.js
@@ -0,0 +1,76 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+add_task(async function resetBeforeTests() {
+  await reset();
+});
+
+add_task(async function get_nonexistent() {
+  await getSubdomainsOK(["a.com", "foo"], []);
+  await reset();
+});
+
+add_task(async function isomorphicDomains() {
+  await set("a.com", "foo", 1);
+  await getSubdomainsOK(["a.com", "foo"], [["a.com", 1]]);
+  await getSubdomainsOK(["http://a.com/huh", "foo"], [["a.com", 1]]);
+  await reset();
+});
+
+add_task(async function names() {
+  await set("a.com", "foo", 1);
+  await getSubdomainsOK(["a.com", "foo"], [["a.com", 1]]);
+
+  await set("a.com", "bar", 2);
+  await getSubdomainsOK(["a.com", "foo"], [["a.com", 1]]);
+  await getSubdomainsOK(["a.com", "bar"], [["a.com", 2]]);
+
+  await setGlobal("foo", 3);
+  await getSubdomainsOK(["a.com", "foo"], [["a.com", 1]]);
+  await getSubdomainsOK(["a.com", "bar"], [["a.com", 2]]);
+  await reset();
+});
+
+add_task(async function subdomains() {
+  await set("a.com", "foo", 1);
+  await set("b.a.com", "foo", 2);
+  await getSubdomainsOK(
+    ["a.com", "foo"],
+    [
+      ["a.com", 1],
+      ["b.a.com", 2],
+    ]
+  );
+  await getSubdomainsOK(["b.a.com", "foo"], [["b.a.com", 2]]);
+  await reset();
+});
+
+add_task(async function privateBrowsing() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await set("b.com", "foo", 5);
+
+  let context = privateLoadContext;
+  await set("a.com", "foo", 6, context);
+  await setGlobal("foo", 7, context);
+  await getSubdomainsOK(["a.com", "foo", context], [["a.com", 6]]);
+  await getSubdomainsOK(["a.com", "bar", context], [["a.com", 2]]);
+  await getSubdomainsOK(["b.com", "foo", context], [["b.com", 5]]);
+
+  await getSubdomainsOK(["a.com", "foo"], [["a.com", 1]]);
+  await getSubdomainsOK(["a.com", "bar"], [["a.com", 2]]);
+  await getSubdomainsOK(["b.com", "foo"], [["b.com", 5]]);
+  await reset();
+});
+
+add_task(async function erroneous() {
+  do_check_throws(() => cps.getBySubdomainAndName(null, "foo", null, {}));
+  do_check_throws(() => cps.getBySubdomainAndName("", "foo", null, {}));
+  do_check_throws(() => cps.getBySubdomainAndName("a.com", "", null, {}));
+  do_check_throws(() => cps.getBySubdomainAndName("a.com", null, null, {}));
+  do_check_throws(() => cps.getBySubdomainAndName("a.com", "foo", null, null));
+  await reset();
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_migrationToSchema4.js b/toolkit/components/contentprefs/tests/unit_cps2/test_migrationToSchema4.js
new file mode 100644
index 0000000000..916fc55498
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_migrationToSchema4.js
@@ -0,0 +1,78 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Dump of version we migrate from
+var schema_version3 = `
+PRAGMA foreign_keys=OFF;
+BEGIN TRANSACTION;
+  CREATE TABLE groups (id INTEGER PRIMARY KEY, name TEXT NOT NULL);
+  INSERT INTO "groups" VALUES(1,'foo.com');
+  INSERT INTO "groups" VALUES(2,'bar.com');
+
+  CREATE TABLE settings (id INTEGER PRIMARY KEY, name TEXT NOT NULL);
+  INSERT INTO "settings" VALUES(1,'zoom-setting');
+  INSERT INTO "settings" VALUES(2,'dir-setting');
+
+  CREATE TABLE prefs (id INTEGER PRIMARY KEY, groupID INTEGER REFERENCES groups(id), settingID INTEGER NOT NULL REFERENCES settings(id), value BLOB);
+  INSERT INTO "prefs" VALUES(1,1,1,0.5);
+  INSERT INTO "prefs" VALUES(2,1,2,'/download/dir');
+  INSERT INTO "prefs" VALUES(3,2,1,0.3);
+  INSERT INTO "prefs" VALUES(4,NULL,1,0.1);
+
+  CREATE INDEX groups_idx ON groups(name);
+  CREATE INDEX settings_idx ON settings(name);
+  CREATE INDEX prefs_idx ON prefs(groupID, settingID);
+COMMIT;`;
+
+function prepareVersion3Schema(callback) {
+  var dbFile = Services.dirsvc.get("ProfD", Ci.nsIFile);
+  dbFile.append("content-prefs.sqlite");
+
+  ok(!dbFile.exists(), "Db should not exist yet.");
+
+  var dbConnection = Services.storage.openDatabase(dbFile);
+  equal(dbConnection.schemaVersion, 0);
+
+  dbConnection.executeSimpleSQL(schema_version3);
+  dbConnection.schemaVersion = 3;
+
+  dbConnection.close();
+}
+
+add_task(async function resetBeforeTests() {
+  prepareVersion3Schema();
+});
+
+// WARNING: Database will reset after every test. This limitation comes from
+// the fact that we ContentPrefService constructor is run only once per test file
+// and so migration will be run only once.
+add_task(async function testMigration() {
+  // Test migrated db content.
+  await schemaVersionIs(CURRENT_DB_VERSION);
+  let dbExpectedState = [
+    [null, "zoom-setting", 0.1],
+    ["bar.com", "zoom-setting", 0.3],
+    ["foo.com", "zoom-setting", 0.5],
+    ["foo.com", "dir-setting", "/download/dir"],
+  ];
+  await dbOK(dbExpectedState);
+
+  // Migrated fields should have timestamp set to 0.
+  await new Promise(resolve =>
+    cps.removeAllDomainsSince(1000, null, makeCallback(resolve))
+  );
+  await dbOK(dbExpectedState);
+
+  await new Promise(resolve =>
+    cps.removeAllDomainsSince(0, null, makeCallback(resolve))
+  );
+  await dbOK([[null, "zoom-setting", 0.1]]);
+
+  // Test that dates are present after migration (column is added).
+  const timestamp = 1234;
+  await setWithDate("a.com", "pref-name", "val", timestamp);
+  let actualTimestamp = await getDate("a.com", "pref-name");
+  equal(actualTimestamp, timestamp);
+  await reset();
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_migrationToSchema5.js b/toolkit/components/contentprefs/tests/unit_cps2/test_migrationToSchema5.js
new file mode 100644
index 0000000000..a904542899
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_migrationToSchema5.js
@@ -0,0 +1,66 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+ChromeUtils.defineESModuleGetters(this, {
+  Sqlite: "resource://gre/modules/Sqlite.sys.mjs",
+});
+
+const MAX_LENGTH = Ci.nsIContentPrefService2.GROUP_NAME_MAX_LENGTH;
+const LONG_DATA_URL = `data:,${new Array(MAX_LENGTH).fill("x").join("")}`;
+
+// Dump of version we migrate from
+const schema_queries = [
+  "PRAGMA foreign_keys=OFF",
+  "CREATE TABLE groups (id INTEGER PRIMARY KEY, name TEXT NOT NULL)",
+  `INSERT INTO groups VALUES (1,'foo.com'),
+                             (2,'bar.com'),
+                             (3,'data:image/png;base64,1234'),
+                             (4,'file:///d/test.file'),
+                             (5,'${LONG_DATA_URL}')`,
+  "CREATE TABLE settings (id INTEGER PRIMARY KEY, name TEXT NOT NULL)",
+  `INSERT INTO settings VALUES (1,'zoom-setting'),
+                               (2,'browser.download.lastDir')`,
+  `CREATE TABLE prefs (id INTEGER PRIMARY KEY,
+                       groupID INTEGER REFERENCES groups(id),
+                       settingID INTEGER NOT NULL REFERENCES settings(id),
+                       value BLOB,
+                       timestamp INTEGER NOT NULL DEFAULT 0)`,
+  `INSERT INTO prefs VALUES (1,1,1,0.5,0),
+                            (2,1,2,'/download/dir',0),
+                            (3,2,1,0.3,0),
+                            (4,NULL,1,0.1,0),
+                            (5,3,2,'/download/dir',0),
+                            (6,4,2,'/download/dir',0),
+                            (7,5,1,0.7,0)`,
+  "CREATE INDEX groups_idx ON groups(name)",
+  "CREATE INDEX settings_idx ON settings(name)",
+  "CREATE INDEX prefs_idx ON prefs(timestamp, groupID, settingID)",
+];
+
+add_setup(async function () {
+  let conn = await Sqlite.openConnection({
+    path: PathUtils.join(PathUtils.profileDir, "content-prefs.sqlite"),
+  });
+  Assert.equal(await conn.getSchemaVersion(), 0);
+  await conn.executeTransaction(async () => {
+    for (let query of schema_queries) {
+      await conn.execute(query);
+    }
+  });
+  await conn.setSchemaVersion(4);
+  await conn.close();
+});
+
+add_task(async function test() {
+  // Test migrated db content.
+  await schemaVersionIs(CURRENT_DB_VERSION);
+  let dbExpectedState = [
+    [null, "zoom-setting", 0.1],
+    ["bar.com", "zoom-setting", 0.3],
+    ["foo.com", "zoom-setting", 0.5],
+    [LONG_DATA_URL.substring(0, MAX_LENGTH - 1), "zoom-setting", 0.7],
+    ["foo.com", "browser.download.lastDir", "/download/dir"],
+  ];
+  await dbOK(dbExpectedState);
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_migrationToSchema6.js b/toolkit/components/contentprefs/tests/unit_cps2/test_migrationToSchema6.js
new file mode 100644
index 0000000000..0dabd5c136
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_migrationToSchema6.js
@@ -0,0 +1,61 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+ChromeUtils.defineESModuleGetters(this, {
+  Sqlite: "resource://gre/modules/Sqlite.sys.mjs",
+});
+
+// Dump of version we migrate from
+const schema_queries = [
+  "PRAGMA foreign_keys=OFF",
+  "CREATE TABLE groups (id INTEGER PRIMARY KEY, name TEXT NOT NULL)",
+  `INSERT INTO groups VALUES (1,'foo.com'),
+                             (2,'bar.com'),
+                             (3,'blob:resource://pdf.js/ed645567-3eea-4ff1-94fd-efb04812afe0'),
+                             (4,'blob:https://chat.mozilla.org/35d6a992-6e18-4957-8216-070c53b9bc83')`,
+  "CREATE TABLE settings (id INTEGER PRIMARY KEY, name TEXT NOT NULL)",
+  `INSERT INTO settings VALUES (1,'zoom-setting'),
+                               (2,'browser.download.lastDir')`,
+  `CREATE TABLE prefs (id INTEGER PRIMARY KEY,
+                       groupID INTEGER REFERENCES groups(id),
+                       settingID INTEGER NOT NULL REFERENCES settings(id),
+                       value BLOB,
+                       timestamp INTEGER NOT NULL DEFAULT 0)`,
+  `INSERT INTO prefs VALUES (1,1,1,0.5,0),
+                            (2,1,2,'/download/dir',0),
+                            (3,2,1,0.3,0),
+                            (4,NULL,1,0.1,0),
+                            (5,3,2,'/download/dir',0),
+                            (6,4,2,'/download/dir',0),
+                            (7,4,1,0.1,0)`,
+  "CREATE INDEX groups_idx ON groups(name)",
+  "CREATE INDEX settings_idx ON settings(name)",
+  "CREATE INDEX prefs_idx ON prefs(timestamp, groupID, settingID)",
+];
+
+add_setup(async function () {
+  let conn = await Sqlite.openConnection({
+    path: PathUtils.join(PathUtils.profileDir, "content-prefs.sqlite"),
+  });
+  Assert.equal(await conn.getSchemaVersion(), 0);
+  await conn.executeTransaction(async () => {
+    for (let query of schema_queries) {
+      await conn.execute(query);
+    }
+  });
+  await conn.setSchemaVersion(5);
+  await conn.close();
+});
+
+add_task(async function test() {
+  // Test migrated db content.
+  await schemaVersionIs(CURRENT_DB_VERSION);
+  let dbExpectedState = [
+    [null, "zoom-setting", 0.1],
+    ["bar.com", "zoom-setting", 0.3],
+    ["foo.com", "zoom-setting", 0.5],
+    ["foo.com", "browser.download.lastDir", "/download/dir"],
+  ];
+  await dbOK(dbExpectedState);
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_observers.js b/toolkit/components/contentprefs/tests/unit_cps2/test_observers.js
new file mode 100644
index 0000000000..cc31cd740a
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_observers.js
@@ -0,0 +1,291 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+Services.prefs.setBoolPref("security.allow_eval_with_system_principal", true);
+registerCleanupFunction(() => {
+  Services.prefs.clearUserPref("security.allow_eval_with_system_principal");
+});
+
+add_task(async function resetBeforeTests() {
+  await reset();
+});
+
+function raceWithIdleDispatch(promise) {
+  return Promise.race([
+    promise,
+    new Promise(resolve => {
+      Services.tm.idleDispatchToMainThread(() => resolve(null));
+    }),
+  ]);
+}
+
+var tests = [
+  async function observerForName_set(context) {
+    let argsPromise;
+    argsPromise = on("Set", ["foo", null, "bar"]);
+    await set("a.com", "foo", 1, context);
+    let args = await argsPromise;
+    observerArgsOK(args.foo, [["a.com", "foo", 1, context.usePrivateBrowsing]]);
+    observerArgsOK(args.null, [
+      ["a.com", "foo", 1, context.usePrivateBrowsing],
+    ]);
+    observerArgsOK(args.bar, []);
+
+    argsPromise = on("Set", ["foo", null, "bar"]);
+    await setGlobal("foo", 2, context);
+    args = await argsPromise;
+    observerArgsOK(args.foo, [[null, "foo", 2, context.usePrivateBrowsing]]);
+    observerArgsOK(args.null, [[null, "foo", 2, context.usePrivateBrowsing]]);
+    observerArgsOK(args.bar, []);
+    await reset();
+  },
+
+  async function observerForName_remove(context) {
+    let argsPromise;
+    await set("a.com", "foo", 1, context);
+    await setGlobal("foo", 2, context);
+
+    argsPromise = on("Removed", ["foo", null, "bar"]);
+    await new Promise(resolve =>
+      cps.removeByDomainAndName(
+        "a.com",
+        "bogus",
+        context,
+        makeCallback(resolve)
+      )
+    );
+    let args = await raceWithIdleDispatch(argsPromise);
+    strictEqual(args, null);
+
+    argsPromise = on("Removed", ["foo", null, "bar"]);
+    await new Promise(resolve =>
+      cps.removeByDomainAndName("a.com", "foo", context, makeCallback(resolve))
+    );
+    args = await argsPromise;
+    observerArgsOK(args.foo, [["a.com", "foo", context.usePrivateBrowsing]]);
+    observerArgsOK(args.null, [["a.com", "foo", context.usePrivateBrowsing]]);
+    observerArgsOK(args.bar, []);
+
+    argsPromise = on("Removed", ["foo", null, "bar"]);
+    await new Promise(resolve =>
+      cps.removeGlobal("foo", context, makeCallback(resolve))
+    );
+    args = await argsPromise;
+    observerArgsOK(args.foo, [[null, "foo", context.usePrivateBrowsing]]);
+    observerArgsOK(args.null, [[null, "foo", context.usePrivateBrowsing]]);
+    observerArgsOK(args.bar, []);
+    await reset();
+  },
+
+  async function observerForName_removeByDomain(context) {
+    let argsPromise;
+    await set("a.com", "foo", 1, context);
+    await set("b.a.com", "bar", 2, context);
+    await setGlobal("foo", 3, context);
+
+    argsPromise = on("Removed", ["foo", null, "bar"]);
+    await new Promise(resolve =>
+      cps.removeByDomain("bogus", context, makeCallback(resolve))
+    );
+    let args = await raceWithIdleDispatch(argsPromise);
+    strictEqual(args, null);
+
+    argsPromise = on("Removed", ["foo", null, "bar"]);
+    await new Promise(resolve =>
+      cps.removeBySubdomain("a.com", context, makeCallback(resolve))
+    );
+    args = await argsPromise;
+    observerArgsOK(args.foo, [["a.com", "foo", context.usePrivateBrowsing]]);
+    observerArgsOK(args.null, [
+      ["a.com", "foo", context.usePrivateBrowsing],
+      ["b.a.com", "bar", context.usePrivateBrowsing],
+    ]);
+    observerArgsOK(args.bar, [["b.a.com", "bar", context.usePrivateBrowsing]]);
+
+    argsPromise = on("Removed", ["foo", null, "bar"]);
+    await new Promise(resolve =>
+      cps.removeAllGlobals(context, makeCallback(resolve))
+    );
+    args = await argsPromise;
+    observerArgsOK(args.foo, [[null, "foo", context.usePrivateBrowsing]]);
+    observerArgsOK(args.null, [[null, "foo", context.usePrivateBrowsing]]);
+    observerArgsOK(args.bar, []);
+    await reset();
+  },
+
+  async function observerForName_removeAllDomains(context) {
+    let argsPromise;
+    await set("a.com", "foo", 1, context);
+    await setGlobal("foo", 2, context);
+    await set("b.com", "bar", 3, context);
+
+    argsPromise = on("Removed", ["foo", null, "bar"]);
+    await new Promise(resolve =>
+      cps.removeAllDomains(context, makeCallback(resolve))
+    );
+    let args = await argsPromise;
+    observerArgsOK(args.foo, [["a.com", "foo", context.usePrivateBrowsing]]);
+    observerArgsOK(args.null, [
+      ["a.com", "foo", context.usePrivateBrowsing],
+      ["b.com", "bar", context.usePrivateBrowsing],
+    ]);
+    observerArgsOK(args.bar, [["b.com", "bar", context.usePrivateBrowsing]]);
+    await reset();
+  },
+
+  async function observerForName_removeByName(context) {
+    let argsPromise;
+    await set("a.com", "foo", 1, context);
+    await set("a.com", "bar", 2, context);
+    await setGlobal("foo", 3, context);
+
+    argsPromise = on("Removed", ["foo", null, "bar"]);
+    await new Promise(resolve =>
+      cps.removeByName("bogus", context, makeCallback(resolve))
+    );
+    let args = await raceWithIdleDispatch(argsPromise);
+    strictEqual(args, null);
+
+    argsPromise = on("Removed", ["foo", null, "bar"]);
+    await new Promise(resolve =>
+      cps.removeByName("foo", context, makeCallback(resolve))
+    );
+    args = await argsPromise;
+    observerArgsOK(args.foo, [
+      ["a.com", "foo", context.usePrivateBrowsing],
+      [null, "foo", context.usePrivateBrowsing],
+    ]);
+    observerArgsOK(args.null, [
+      ["a.com", "foo", context.usePrivateBrowsing],
+      [null, "foo", context.usePrivateBrowsing],
+    ]);
+    observerArgsOK(args.bar, []);
+    await reset();
+  },
+
+  async function removeObserverForName(context) {
+    let { promise, observers } = onEx("Set", ["foo", null, "bar"]);
+    cps.removeObserverForName("foo", observers.foo);
+    await set("a.com", "foo", 1, context);
+    await wait();
+    let args = await promise;
+    observerArgsOK(args.foo, []);
+    observerArgsOK(args.null, [
+      ["a.com", "foo", 1, context.usePrivateBrowsing],
+    ]);
+    observerArgsOK(args.bar, []);
+    args.reset();
+
+    cps.removeObserverForName(null, args.null.observer);
+    await set("a.com", "foo", 2, context);
+    await wait();
+    observerArgsOK(args.foo, []);
+    observerArgsOK(args.null, []);
+    observerArgsOK(args.bar, []);
+    args.reset();
+    await reset();
+  },
+];
+
+// These tests are for functionality that doesn't behave the same way in private and public
+// contexts, so the expected results cannot be automatically generated like the previous tests.
+var specialTests = [
+  async function observerForName_removeAllDomainsSince() {
+    let argsPromise;
+    await setWithDate("a.com", "foo", 1, 100, null);
+    await setWithDate("b.com", "foo", 2, 200, null);
+    await setWithDate("c.com", "foo", 3, 300, null);
+
+    await setWithDate("a.com", "bar", 1, 0, null);
+    await setWithDate("b.com", "bar", 2, 100, null);
+    await setWithDate("c.com", "bar", 3, 200, null);
+    await setGlobal("foo", 2, null);
+
+    argsPromise = on("Removed", ["foo", "bar", null]);
+    await new Promise(resolve =>
+      cps.removeAllDomainsSince(200, null, makeCallback(resolve))
+    );
+
+    let args = await argsPromise;
+
+    observerArgsOK(args.foo, [
+      ["b.com", "foo", false],
+      ["c.com", "foo", false],
+    ]);
+    observerArgsOK(args.bar, [["c.com", "bar", false]]);
+    observerArgsOK(args.null, [
+      ["b.com", "foo", false],
+      ["c.com", "bar", false],
+      ["c.com", "foo", false],
+    ]);
+    await reset();
+  },
+
+  async function observerForName_removeAllDomainsSince_private() {
+    let argsPromise;
+    let context = privateLoadContext;
+    await setWithDate("a.com", "foo", 1, 100, context);
+    await setWithDate("b.com", "foo", 2, 200, context);
+    await setWithDate("c.com", "foo", 3, 300, context);
+
+    await setWithDate("a.com", "bar", 1, 0, context);
+    await setWithDate("b.com", "bar", 2, 100, context);
+    await setWithDate("c.com", "bar", 3, 200, context);
+    await setGlobal("foo", 2, context);
+
+    argsPromise = on("Removed", ["foo", "bar", null]);
+    await new Promise(resolve =>
+      cps.removeAllDomainsSince(200, context, makeCallback(resolve))
+    );
+
+    let args = await argsPromise;
+
+    observerArgsOK(args.foo, [
+      ["a.com", "foo", true],
+      ["b.com", "foo", true],
+      ["c.com", "foo", true],
+    ]);
+    observerArgsOK(args.bar, [
+      ["a.com", "bar", true],
+      ["b.com", "bar", true],
+      ["c.com", "bar", true],
+    ]);
+    observerArgsOK(args.null, [
+      ["a.com", "foo", true],
+      ["a.com", "bar", true],
+      ["b.com", "foo", true],
+      ["b.com", "bar", true],
+      ["c.com", "foo", true],
+      ["c.com", "bar", true],
+    ]);
+    await reset();
+  },
+];
+
+for (let i = 0; i < tests.length; i++) {
+  // Generate two wrappers of each test function that invoke the original test with an
+  // appropriate privacy context.
+  /* eslint-disable no-eval */
+  var pub = eval(
+    "var f = async function " +
+      tests[i].name +
+      "() { await tests[" +
+      i +
+      "](privateLoadContext); }; f"
+  );
+  var priv = eval(
+    "var f = async function " +
+      tests[i].name +
+      "_private() { await tests[" +
+      i +
+      "](privateLoadContext); }; f"
+  );
+  /* eslint-enable no-eval */
+  add_task(pub);
+  add_task(priv);
+}
+
+for (let test of specialTests) {
+  add_task(test);
+}
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_remove.js b/toolkit/components/contentprefs/tests/unit_cps2/test_remove.js
new file mode 100644
index 0000000000..0c9e797903
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_remove.js
@@ -0,0 +1,267 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+add_task(async function resetBeforeTests() {
+  await reset();
+});
+
+add_task(async function nonexistent() {
+  await set("a.com", "foo", 1);
+  await setGlobal("foo", 2);
+
+  await new Promise(resolve =>
+    cps.removeByDomainAndName("a.com", "bogus", null, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "foo", 1],
+    [null, "foo", 2],
+  ]);
+  await getOK(["a.com", "foo"], 1);
+  await getGlobalOK(["foo"], 2);
+
+  await new Promise(resolve =>
+    cps.removeBySubdomainAndName("a.com", "bogus", null, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "foo", 1],
+    [null, "foo", 2],
+  ]);
+  await getOK(["a.com", "foo"], 1);
+  await getGlobalOK(["foo"], 2);
+
+  await new Promise(resolve =>
+    cps.removeGlobal("bogus", null, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "foo", 1],
+    [null, "foo", 2],
+  ]);
+  await getOK(["a.com", "foo"], 1);
+  await getGlobalOK(["foo"], 2);
+
+  await new Promise(resolve =>
+    cps.removeByDomainAndName("bogus", "bogus", null, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "foo", 1],
+    [null, "foo", 2],
+  ]);
+  await getOK(["a.com", "foo"], 1);
+  await getGlobalOK(["foo"], 2);
+  await reset();
+});
+
+add_task(async function isomorphicDomains() {
+  await set("a.com", "foo", 1);
+  await new Promise(resolve =>
+    cps.removeByDomainAndName("a.com", "foo", null, makeCallback(resolve))
+  );
+  await dbOK([]);
+  await getOK(["a.com", "foo"], undefined);
+
+  await set("a.com", "foo", 2);
+  await new Promise(resolve =>
+    cps.removeByDomainAndName(
+      "http://a.com/huh",
+      "foo",
+      null,
+      makeCallback(resolve)
+    )
+  );
+  await dbOK([]);
+  await getOK(["a.com", "foo"], undefined);
+  await reset();
+});
+
+add_task(async function names() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+
+  await new Promise(resolve =>
+    cps.removeByDomainAndName("a.com", "foo", null, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "bar", 2],
+    [null, "foo", 3],
+    [null, "bar", 4],
+  ]);
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], 2);
+  await getGlobalOK(["foo"], 3);
+  await getGlobalOK(["bar"], 4);
+
+  await new Promise(resolve =>
+    cps.removeGlobal("foo", null, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "bar", 2],
+    [null, "bar", 4],
+  ]);
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], 2);
+  await getGlobalOK(["foo"], undefined);
+  await getGlobalOK(["bar"], 4);
+
+  await new Promise(resolve =>
+    cps.removeByDomainAndName("a.com", "bar", null, makeCallback(resolve))
+  );
+  await dbOK([[null, "bar", 4]]);
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], undefined);
+  await getGlobalOK(["foo"], undefined);
+  await getGlobalOK(["bar"], 4);
+
+  await new Promise(resolve =>
+    cps.removeGlobal("bar", null, makeCallback(resolve))
+  );
+  await dbOK([]);
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], undefined);
+  await getGlobalOK(["foo"], undefined);
+  await getGlobalOK(["bar"], undefined);
+  await reset();
+});
+
+add_task(async function subdomains() {
+  await set("a.com", "foo", 1);
+  await set("b.a.com", "foo", 2);
+  await new Promise(resolve =>
+    cps.removeByDomainAndName("a.com", "foo", null, makeCallback(resolve))
+  );
+  await dbOK([["b.a.com", "foo", 2]]);
+  await getSubdomainsOK(["a.com", "foo"], [["b.a.com", 2]]);
+  await getSubdomainsOK(["b.a.com", "foo"], [["b.a.com", 2]]);
+
+  await set("a.com", "foo", 3);
+  await new Promise(resolve =>
+    cps.removeBySubdomainAndName("a.com", "foo", null, makeCallback(resolve))
+  );
+  await dbOK([]);
+  await getSubdomainsOK(["a.com", "foo"], []);
+  await getSubdomainsOK(["b.a.com", "foo"], []);
+
+  await set("a.com", "foo", 4);
+  await set("b.a.com", "foo", 5);
+  await new Promise(resolve =>
+    cps.removeByDomainAndName("b.a.com", "foo", null, makeCallback(resolve))
+  );
+  await dbOK([["a.com", "foo", 4]]);
+  await getSubdomainsOK(["a.com", "foo"], [["a.com", 4]]);
+  await getSubdomainsOK(["b.a.com", "foo"], []);
+
+  await set("b.a.com", "foo", 6);
+  await new Promise(resolve =>
+    cps.removeBySubdomainAndName("b.a.com", "foo", null, makeCallback(resolve))
+  );
+  await dbOK([["a.com", "foo", 4]]);
+  await getSubdomainsOK(["a.com", "foo"], [["a.com", 4]]);
+  await getSubdomainsOK(["b.a.com", "foo"], []);
+  await reset();
+});
+
+add_task(async function privateBrowsing() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await setGlobal("qux", 5);
+  await set("b.com", "foo", 6);
+  await set("b.com", "bar", 7);
+
+  let context = privateLoadContext;
+  await set("a.com", "foo", 8, context);
+  await setGlobal("foo", 9, context);
+  await new Promise(resolve =>
+    cps.removeByDomainAndName("a.com", "foo", context, makeCallback(resolve))
+  );
+  await new Promise(resolve =>
+    cps.removeGlobal("foo", context, makeCallback(resolve))
+  );
+  await new Promise(resolve =>
+    cps.removeGlobal("qux", context, makeCallback(resolve))
+  );
+  await new Promise(resolve =>
+    cps.removeByDomainAndName("b.com", "foo", context, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "bar", 2],
+    [null, "bar", 4],
+    ["b.com", "bar", 7],
+  ]);
+  await getOK(["a.com", "foo", context], undefined);
+  await getOK(["a.com", "bar", context], 2);
+  await getGlobalOK(["foo", context], undefined);
+  await getGlobalOK(["bar", context], 4);
+  await getGlobalOK(["qux", context], undefined);
+  await getOK(["b.com", "foo", context], undefined);
+  await getOK(["b.com", "bar", context], 7);
+
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], 2);
+  await getGlobalOK(["foo"], undefined);
+  await getGlobalOK(["bar"], 4);
+  await getGlobalOK(["qux"], undefined);
+  await getOK(["b.com", "foo"], undefined);
+  await getOK(["b.com", "bar"], 7);
+  await reset();
+});
+
+add_task(async function erroneous() {
+  do_check_throws(() => cps.removeByDomainAndName(null, "foo", null));
+  do_check_throws(() => cps.removeByDomainAndName("", "foo", null));
+  do_check_throws(() =>
+    cps.removeByDomainAndName("a.com", "foo", null, "bogus")
+  );
+  do_check_throws(() => cps.removeBySubdomainAndName(null, "foo", null));
+  do_check_throws(() => cps.removeBySubdomainAndName("", "foo", null));
+  do_check_throws(() =>
+    cps.removeBySubdomainAndName("a.com", "foo", null, "bogus")
+  );
+  do_check_throws(() => cps.removeGlobal("", null));
+  do_check_throws(() => cps.removeGlobal(null, null));
+  do_check_throws(() => cps.removeGlobal("foo", null, "bogus"));
+  await reset();
+});
+
+add_task(async function removeByDomainAndName_invalidateCache() {
+  await set("a.com", "foo", 1);
+  getCachedOK(["a.com", "foo"], true, 1);
+  let promiseRemoved = new Promise(resolve => {
+    cps.removeByDomainAndName("a.com", "foo", null, makeCallback(resolve));
+  });
+  getCachedOK(["a.com", "foo"], false);
+  await promiseRemoved;
+  await reset();
+});
+
+add_task(async function removeBySubdomainAndName_invalidateCache() {
+  await set("a.com", "foo", 1);
+  await set("b.a.com", "foo", 2);
+  getCachedSubdomainsOK(
+    ["a.com", "foo"],
+    [
+      ["a.com", 1],
+      ["b.a.com", 2],
+    ]
+  );
+  let promiseRemoved = new Promise(resolve => {
+    cps.removeBySubdomainAndName("a.com", "foo", null, makeCallback(resolve));
+  });
+  getCachedSubdomainsOK(["a.com", "foo"], []);
+  await promiseRemoved;
+  await reset();
+});
+
+add_task(async function removeGlobal_invalidateCache() {
+  await setGlobal("foo", 1);
+  getCachedGlobalOK(["foo"], true, 1);
+  let promiseRemoved = new Promise(resolve => {
+    cps.removeGlobal("foo", null, makeCallback(resolve));
+  });
+  getCachedGlobalOK(["foo"], false);
+  await promiseRemoved;
+  await reset();
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_removeAllDomains.js b/toolkit/components/contentprefs/tests/unit_cps2/test_removeAllDomains.js
new file mode 100644
index 0000000000..7615757f97
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_removeAllDomains.js
@@ -0,0 +1,94 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+add_task(async function resetBeforeTests() {
+  await reset();
+});
+
+add_task(async function nonexistent() {
+  await setGlobal("foo", 1);
+  await new Promise(resolve =>
+    cps.removeAllDomains(null, makeCallback(resolve))
+  );
+  await dbOK([[null, "foo", 1]]);
+  await getGlobalOK(["foo"], 1);
+  await reset();
+});
+
+add_task(async function domains() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await set("b.com", "foo", 5);
+  await set("b.com", "bar", 6);
+
+  await new Promise(resolve =>
+    cps.removeAllDomains(null, makeCallback(resolve))
+  );
+  await dbOK([
+    [null, "foo", 3],
+    [null, "bar", 4],
+  ]);
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], undefined);
+  await getGlobalOK(["foo"], 3);
+  await getGlobalOK(["bar"], 4);
+  await getOK(["b.com", "foo"], undefined);
+  await getOK(["b.com", "bar"], undefined);
+  await reset();
+});
+
+add_task(async function privateBrowsing() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await set("b.com", "foo", 5);
+
+  let context = privateLoadContext;
+  await set("a.com", "foo", 6, context);
+  await setGlobal("foo", 7, context);
+  await new Promise(resolve =>
+    cps.removeAllDomains(context, makeCallback(resolve))
+  );
+  await dbOK([
+    [null, "foo", 3],
+    [null, "bar", 4],
+  ]);
+  await getOK(["a.com", "foo", context], undefined);
+  await getOK(["a.com", "bar", context], undefined);
+  await getGlobalOK(["foo", context], 7);
+  await getGlobalOK(["bar", context], 4);
+  await getOK(["b.com", "foo", context], undefined);
+
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], undefined);
+  await getGlobalOK(["foo"], 3);
+  await getGlobalOK(["bar"], 4);
+  await getOK(["b.com", "foo"], undefined);
+  await reset();
+});
+
+add_task(async function erroneous() {
+  do_check_throws(() => cps.removeAllDomains(null, "bogus"));
+  await reset();
+});
+
+add_task(async function invalidateCache() {
+  await set("a.com", "foo", 1);
+  await set("b.com", "bar", 2);
+  await setGlobal("baz", 3);
+  getCachedOK(["a.com", "foo"], true, 1);
+  getCachedOK(["b.com", "bar"], true, 2);
+  getCachedGlobalOK(["baz"], true, 3);
+  let promiseRemoved = new Promise(resolve =>
+    cps.removeAllDomains(null, makeCallback(resolve))
+  );
+  getCachedOK(["a.com", "foo"], false);
+  getCachedOK(["b.com", "bar"], false);
+  getCachedGlobalOK(["baz"], true, 3);
+  await promiseRemoved;
+  await reset();
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_removeAllDomainsSince.js b/toolkit/components/contentprefs/tests/unit_cps2/test_removeAllDomainsSince.js
new file mode 100644
index 0000000000..a78d35054b
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_removeAllDomainsSince.js
@@ -0,0 +1,123 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+add_task(async function resetBeforeTests() {
+  await reset();
+});
+
+add_task(async function nonexistent() {
+  await setGlobal("foo", 1);
+  await new Promise(resolve =>
+    cps.removeAllDomainsSince(0, null, makeCallback(resolve))
+  );
+  await getGlobalOK(["foo"], 1);
+  await reset();
+});
+
+add_task(async function domainsAll() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await set("b.com", "foo", 5);
+  await set("b.com", "bar", 6);
+
+  await new Promise(resolve =>
+    cps.removeAllDomainsSince(0, null, makeCallback(resolve))
+  );
+  await dbOK([
+    [null, "foo", 3],
+    [null, "bar", 4],
+  ]);
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], undefined);
+  await getGlobalOK(["foo"], 3);
+  await getGlobalOK(["bar"], 4);
+  await getOK(["b.com", "foo"], undefined);
+  await getOK(["b.com", "bar"], undefined);
+  await reset();
+});
+
+add_task(async function domainsWithDate() {
+  await setWithDate("a.com", "foobar", 0, 0);
+  await setWithDate("a.com", "foo", 1, 1000);
+  await setWithDate("a.com", "bar", 2, 4000);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await setWithDate("b.com", "foo", 5, 2000);
+  await setWithDate("b.com", "bar", 6, 3000);
+  await setWithDate("b.com", "foobar", 7, 1000);
+
+  await new Promise(resolve =>
+    cps.removeAllDomainsSince(2000, null, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "foobar", 0],
+    ["a.com", "foo", 1],
+    [null, "foo", 3],
+    [null, "bar", 4],
+    ["b.com", "foobar", 7],
+  ]);
+  await reset();
+});
+
+add_task(async function privateBrowsing() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await set("b.com", "foo", 5);
+
+  let context = privateLoadContext;
+  await set("a.com", "foo", 6, context);
+  await setGlobal("foo", 7, context);
+  await new Promise(resolve =>
+    cps.removeAllDomainsSince(0, context, makeCallback(resolve))
+  );
+  await dbOK([
+    [null, "foo", 3],
+    [null, "bar", 4],
+  ]);
+  await getOK(["a.com", "foo", context], undefined);
+  await getOK(["a.com", "bar", context], undefined);
+  await getGlobalOK(["foo", context], 7);
+  await getGlobalOK(["bar", context], 4);
+  await getOK(["b.com", "foo", context], undefined);
+
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], undefined);
+  await getGlobalOK(["foo"], 3);
+  await getGlobalOK(["bar"], 4);
+  await getOK(["b.com", "foo"], undefined);
+  await reset();
+});
+
+add_task(async function erroneous() {
+  do_check_throws(() => cps.removeAllDomainsSince(null, "bogus"));
+  await reset();
+});
+
+add_task(async function invalidateCache() {
+  await setWithDate("a.com", "foobar", 0, 0);
+  await setWithDate("a.com", "foo", 1, 1000);
+  await setWithDate("a.com", "bar", 2, 4000);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await setWithDate("b.com", "foo", 5, 2000);
+  await setWithDate("b.com", "bar", 6, 3000);
+  await setWithDate("b.com", "foobar", 7, 1000);
+  let clearPromise = new Promise(resolve => {
+    cps.removeAllDomainsSince(0, null, makeCallback(resolve));
+  });
+  getCachedOK(["a.com", "foobar"], false);
+  getCachedOK(["a.com", "foo"], false);
+  getCachedOK(["a.com", "bar"], false);
+  getCachedGlobalOK(["foo"], true, 3);
+  getCachedGlobalOK(["bar"], true, 4);
+  getCachedOK(["b.com", "foo"], false);
+  getCachedOK(["b.com", "bar"], false);
+  getCachedOK(["b.com", "foobar"], false);
+  await clearPromise;
+  await reset();
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_removeByDomain.js b/toolkit/components/contentprefs/tests/unit_cps2/test_removeByDomain.js
new file mode 100644
index 0000000000..b68d589dbf
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_removeByDomain.js
@@ -0,0 +1,229 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+add_task(async function resetBeforeTests() {
+  await reset();
+});
+
+add_task(async function nonexistent() {
+  await set("a.com", "foo", 1);
+  await setGlobal("foo", 2);
+
+  await new Promise(resolve =>
+    cps.removeByDomain("bogus", null, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "foo", 1],
+    [null, "foo", 2],
+  ]);
+  await getOK(["a.com", "foo"], 1);
+  await getGlobalOK(["foo"], 2);
+
+  await new Promise(resolve =>
+    cps.removeBySubdomain("bogus", null, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "foo", 1],
+    [null, "foo", 2],
+  ]);
+  await getOK(["a.com", "foo"], 1);
+  await getGlobalOK(["foo"], 2);
+  await reset();
+});
+
+add_task(async function isomorphicDomains() {
+  await set("a.com", "foo", 1);
+  await new Promise(resolve =>
+    cps.removeByDomain("a.com", null, makeCallback(resolve))
+  );
+  await dbOK([]);
+  await getOK(["a.com", "foo"], undefined);
+
+  await set("a.com", "foo", 2);
+  await new Promise(resolve =>
+    cps.removeByDomain("http://a.com/huh", null, makeCallback(resolve))
+  );
+  await dbOK([]);
+  await getOK(["a.com", "foo"], undefined);
+  await reset();
+});
+
+add_task(async function domains() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await set("b.com", "foo", 5);
+  await set("b.com", "bar", 6);
+
+  await new Promise(resolve =>
+    cps.removeByDomain("a.com", null, makeCallback(resolve))
+  );
+  await dbOK([
+    [null, "foo", 3],
+    [null, "bar", 4],
+    ["b.com", "foo", 5],
+    ["b.com", "bar", 6],
+  ]);
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], undefined);
+  await getGlobalOK(["foo"], 3);
+  await getGlobalOK(["bar"], 4);
+  await getOK(["b.com", "foo"], 5);
+  await getOK(["b.com", "bar"], 6);
+
+  await new Promise(resolve =>
+    cps.removeAllGlobals(null, makeCallback(resolve))
+  );
+  await dbOK([
+    ["b.com", "foo", 5],
+    ["b.com", "bar", 6],
+  ]);
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], undefined);
+  await getGlobalOK(["foo"], undefined);
+  await getGlobalOK(["bar"], undefined);
+  await getOK(["b.com", "foo"], 5);
+  await getOK(["b.com", "bar"], 6);
+
+  await new Promise(resolve =>
+    cps.removeByDomain("b.com", null, makeCallback(resolve))
+  );
+  await dbOK([]);
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], undefined);
+  await getGlobalOK(["foo"], undefined);
+  await getGlobalOK(["bar"], undefined);
+  await getOK(["b.com", "foo"], undefined);
+  await getOK(["b.com", "bar"], undefined);
+  await reset();
+});
+
+add_task(async function subdomains() {
+  await set("a.com", "foo", 1);
+  await set("b.a.com", "foo", 2);
+  await new Promise(resolve =>
+    cps.removeByDomain("a.com", null, makeCallback(resolve))
+  );
+  await dbOK([["b.a.com", "foo", 2]]);
+  await getSubdomainsOK(["a.com", "foo"], [["b.a.com", 2]]);
+  await getSubdomainsOK(["b.a.com", "foo"], [["b.a.com", 2]]);
+
+  await set("a.com", "foo", 3);
+  await new Promise(resolve =>
+    cps.removeBySubdomain("a.com", null, makeCallback(resolve))
+  );
+  await dbOK([]);
+  await getSubdomainsOK(["a.com", "foo"], []);
+  await getSubdomainsOK(["b.a.com", "foo"], []);
+
+  await set("a.com", "foo", 4);
+  await set("b.a.com", "foo", 5);
+  await new Promise(resolve =>
+    cps.removeByDomain("b.a.com", null, makeCallback(resolve))
+  );
+  await dbOK([["a.com", "foo", 4]]);
+  await getSubdomainsOK(["a.com", "foo"], [["a.com", 4]]);
+  await getSubdomainsOK(["b.a.com", "foo"], []);
+
+  await set("b.a.com", "foo", 6);
+  await new Promise(resolve =>
+    cps.removeBySubdomain("b.a.com", null, makeCallback(resolve))
+  );
+  await dbOK([["a.com", "foo", 4]]);
+  await getSubdomainsOK(["a.com", "foo"], [["a.com", 4]]);
+  await getSubdomainsOK(["b.a.com", "foo"], []);
+  await reset();
+});
+
+add_task(async function privateBrowsing() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await set("b.com", "foo", 5);
+
+  let context = privateLoadContext;
+  await set("a.com", "foo", 6, context);
+  await set("b.com", "foo", 7, context);
+  await setGlobal("foo", 8, context);
+  await new Promise(resolve =>
+    cps.removeByDomain("a.com", context, makeCallback(resolve))
+  );
+  await getOK(["b.com", "foo", context], 7);
+  await getGlobalOK(["foo", context], 8);
+  await new Promise(resolve =>
+    cps.removeAllGlobals(context, makeCallback(resolve))
+  );
+  await dbOK([["b.com", "foo", 5]]);
+  await getOK(["a.com", "foo", context], undefined);
+  await getOK(["a.com", "bar", context], undefined);
+  await getGlobalOK(["foo", context], undefined);
+  await getGlobalOK(["bar", context], undefined);
+  await getOK(["b.com", "foo", context], 5);
+
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], undefined);
+  await getGlobalOK(["foo"], undefined);
+  await getGlobalOK(["bar"], undefined);
+  await getOK(["b.com", "foo"], 5);
+  await reset();
+});
+
+add_task(async function erroneous() {
+  do_check_throws(() => cps.removeByDomain(null, null));
+  do_check_throws(() => cps.removeByDomain("", null));
+  do_check_throws(() => cps.removeByDomain("a.com", null, "bogus"));
+  do_check_throws(() => cps.removeBySubdomain(null, null));
+  do_check_throws(() => cps.removeBySubdomain("", null));
+  do_check_throws(() => cps.removeBySubdomain("a.com", null, "bogus"));
+  do_check_throws(() => cps.removeAllGlobals(null, "bogus"));
+  await reset();
+});
+
+add_task(async function removeByDomain_invalidateCache() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  getCachedOK(["a.com", "foo"], true, 1);
+  getCachedOK(["a.com", "bar"], true, 2);
+  let promiseRemoved = new Promise(resolve => {
+    cps.removeByDomain("a.com", null, makeCallback(resolve));
+  });
+  getCachedOK(["a.com", "foo"], false);
+  getCachedOK(["a.com", "bar"], false);
+  await promiseRemoved;
+  await reset();
+});
+
+add_task(async function removeBySubdomain_invalidateCache() {
+  await set("a.com", "foo", 1);
+  await set("b.a.com", "foo", 2);
+  getCachedSubdomainsOK(
+    ["a.com", "foo"],
+    [
+      ["a.com", 1],
+      ["b.a.com", 2],
+    ]
+  );
+  let promiseRemoved = new Promise(resolve => {
+    cps.removeBySubdomain("a.com", null, makeCallback(resolve));
+  });
+  getCachedSubdomainsOK(["a.com", "foo"], []);
+  await promiseRemoved;
+  await reset();
+});
+
+add_task(async function removeAllGlobals_invalidateCache() {
+  await setGlobal("foo", 1);
+  await setGlobal("bar", 2);
+  getCachedGlobalOK(["foo"], true, 1);
+  getCachedGlobalOK(["bar"], true, 2);
+  let promiseRemoved = new Promise(resolve => {
+    cps.removeAllGlobals(null, makeCallback(resolve));
+  });
+  getCachedGlobalOK(["foo"], false);
+  getCachedGlobalOK(["bar"], false);
+  await promiseRemoved;
+  await reset();
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_removeByName.js b/toolkit/components/contentprefs/tests/unit_cps2/test_removeByName.js
new file mode 100644
index 0000000000..b7fe310802
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_removeByName.js
@@ -0,0 +1,102 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+add_task(async function resetBeforeTests() {
+  await reset();
+});
+
+add_task(async function nonexistent() {
+  await set("a.com", "foo", 1);
+  await setGlobal("foo", 2);
+
+  await new Promise(resolve =>
+    cps.removeByName("bogus", null, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "foo", 1],
+    [null, "foo", 2],
+  ]);
+  await getOK(["a.com", "foo"], 1);
+  await getGlobalOK(["foo"], 2);
+  await reset();
+});
+
+add_task(async function names() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await set("b.com", "foo", 5);
+  await set("b.com", "bar", 6);
+
+  await new Promise(resolve =>
+    cps.removeByName("foo", null, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "bar", 2],
+    [null, "bar", 4],
+    ["b.com", "bar", 6],
+  ]);
+  await getOK(["a.com", "foo"], undefined);
+  await getOK(["a.com", "bar"], 2);
+  await getGlobalOK(["foo"], undefined);
+  await getGlobalOK(["bar"], 4);
+  await getOK(["b.com", "foo"], undefined);
+  await getOK(["b.com", "bar"], 6);
+  await reset();
+});
+
+add_task(async function privateBrowsing() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await set("b.com", "foo", 5);
+  await set("b.com", "bar", 6);
+
+  let context = privateLoadContext;
+  await set("a.com", "foo", 7, context);
+  await setGlobal("foo", 8, context);
+  await set("b.com", "bar", 9, context);
+  await new Promise(resolve =>
+    cps.removeByName("bar", context, makeCallback(resolve))
+  );
+  await dbOK([
+    ["a.com", "foo", 1],
+    [null, "foo", 3],
+    ["b.com", "foo", 5],
+  ]);
+  await getOK(["a.com", "foo", context], 7);
+  await getOK(["a.com", "bar", context], undefined);
+  await getGlobalOK(["foo", context], 8);
+  await getGlobalOK(["bar", context], undefined);
+  await getOK(["b.com", "foo", context], 5);
+  await getOK(["b.com", "bar", context], undefined);
+
+  await getOK(["a.com", "foo"], 1);
+  await getOK(["a.com", "bar"], undefined);
+  await getGlobalOK(["foo"], 3);
+  await getGlobalOK(["bar"], undefined);
+  await getOK(["b.com", "foo"], 5);
+  await getOK(["b.com", "bar"], undefined);
+  await reset();
+});
+
+add_task(async function erroneous() {
+  do_check_throws(() => cps.removeByName("", null));
+  do_check_throws(() => cps.removeByName(null, null));
+  do_check_throws(() => cps.removeByName("foo", null, "bogus"));
+  await reset();
+});
+
+add_task(async function invalidateCache() {
+  await set("a.com", "foo", 1);
+  await set("b.com", "foo", 2);
+  getCachedOK(["a.com", "foo"], true, 1);
+  getCachedOK(["b.com", "foo"], true, 2);
+  cps.removeByName("foo", null, makeCallback());
+  getCachedOK(["a.com", "foo"], false);
+  getCachedOK(["b.com", "foo"], false);
+  await reset();
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/test_setGet.js b/toolkit/components/contentprefs/tests/unit_cps2/test_setGet.js
new file mode 100644
index 0000000000..9d8dff9fda
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/test_setGet.js
@@ -0,0 +1,234 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+add_task(async function resetBeforeTests() {
+  await reset();
+});
+
+add_task(async function get_nonexistent() {
+  await getOK(["a.com", "foo"], undefined);
+  await getGlobalOK(["foo"], undefined);
+  await reset();
+});
+
+add_task(async function isomorphicDomains() {
+  await set("a.com", "foo", 1);
+  await dbOK([["a.com", "foo", 1]]);
+  await getOK(["a.com", "foo"], 1);
+  await getOK(["http://a.com/huh", "foo"], 1, "a.com");
+
+  await set("http://a.com/huh", "foo", 2);
+  await dbOK([["a.com", "foo", 2]]);
+  await getOK(["a.com", "foo"], 2);
+  await getOK(["http://a.com/yeah", "foo"], 2, "a.com");
+  await reset();
+});
+
+add_task(async function names() {
+  await set("a.com", "foo", 1);
+  await dbOK([["a.com", "foo", 1]]);
+  await getOK(["a.com", "foo"], 1);
+
+  await set("a.com", "bar", 2);
+  await dbOK([
+    ["a.com", "foo", 1],
+    ["a.com", "bar", 2],
+  ]);
+  await getOK(["a.com", "foo"], 1);
+  await getOK(["a.com", "bar"], 2);
+
+  await setGlobal("foo", 3);
+  await dbOK([
+    ["a.com", "foo", 1],
+    ["a.com", "bar", 2],
+    [null, "foo", 3],
+  ]);
+  await getOK(["a.com", "foo"], 1);
+  await getOK(["a.com", "bar"], 2);
+  await getGlobalOK(["foo"], 3);
+
+  await setGlobal("bar", 4);
+  await dbOK([
+    ["a.com", "foo", 1],
+    ["a.com", "bar", 2],
+    [null, "foo", 3],
+    [null, "bar", 4],
+  ]);
+  await getOK(["a.com", "foo"], 1);
+  await getOK(["a.com", "bar"], 2);
+  await getGlobalOK(["foo"], 3);
+  await getGlobalOK(["bar"], 4);
+  await reset();
+});
+
+add_task(async function subdomains() {
+  await set("a.com", "foo", 1);
+  await set("b.a.com", "foo", 2);
+  await dbOK([
+    ["a.com", "foo", 1],
+    ["b.a.com", "foo", 2],
+  ]);
+  await getOK(["a.com", "foo"], 1);
+  await getOK(["b.a.com", "foo"], 2);
+  await reset();
+});
+
+add_task(async function privateBrowsing() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await setGlobal("foo", 3);
+  await setGlobal("bar", 4);
+  await set("b.com", "foo", 5);
+
+  let context = privateLoadContext;
+  await set("a.com", "foo", 6, context);
+  await setGlobal("foo", 7, context);
+  await dbOK([
+    ["a.com", "foo", 1],
+    ["a.com", "bar", 2],
+    [null, "foo", 3],
+    [null, "bar", 4],
+    ["b.com", "foo", 5],
+  ]);
+  await getOK(["a.com", "foo", context], 6, "a.com");
+  await getOK(["a.com", "bar", context], 2);
+  await getGlobalOK(["foo", context], 7);
+  await getGlobalOK(["bar", context], 4);
+  await getOK(["b.com", "foo", context], 5);
+
+  await getOK(["a.com", "foo"], 1);
+  await getOK(["a.com", "bar"], 2);
+  await getGlobalOK(["foo"], 3);
+  await getGlobalOK(["bar"], 4);
+  await getOK(["b.com", "foo"], 5);
+  await reset();
+});
+
+add_task(async function set_erroneous() {
+  do_check_throws(() => cps.set(null, "foo", 1, null));
+  do_check_throws(() => cps.set("", "foo", 1, null));
+  do_check_throws(() => cps.set("a.com", "", 1, null));
+  do_check_throws(() => cps.set("a.com", null, 1, null));
+  do_check_throws(() => cps.set("a.com", "foo", undefined, null));
+  do_check_throws(() => cps.set("a.com", "foo", 1, null, "bogus"));
+  do_check_throws(() => cps.setGlobal("", 1, null));
+  do_check_throws(() => cps.setGlobal(null, 1, null));
+  do_check_throws(() => cps.setGlobal("foo", undefined, null));
+  do_check_throws(() => cps.setGlobal("foo", 1, null, "bogus"));
+  await reset();
+});
+
+add_task(async function get_erroneous() {
+  do_check_throws(() => cps.getByDomainAndName(null, "foo", null, {}));
+  do_check_throws(() => cps.getByDomainAndName("", "foo", null, {}));
+  do_check_throws(() => cps.getByDomainAndName("a.com", "", null, {}));
+  do_check_throws(() => cps.getByDomainAndName("a.com", null, null, {}));
+  do_check_throws(() => cps.getByDomainAndName("a.com", "foo", null, null));
+  do_check_throws(() => cps.getGlobal("", null, {}));
+  do_check_throws(() => cps.getGlobal(null, null, {}));
+  do_check_throws(() => cps.getGlobal("foo", null, null));
+  await reset();
+});
+
+add_task(async function set_invalidateCache() {
+  // (1) Set a pref and wait for it to finish.
+  await set("a.com", "foo", 1);
+
+  // (2) It should be cached.
+  getCachedOK(["a.com", "foo"], true, 1);
+
+  // (3) Set the pref to a new value but don't wait for it to finish.
+  cps.set("a.com", "foo", 2, null, {
+    handleCompletion() {
+      // (6) The pref should be cached after setting it.
+      getCachedOK(["a.com", "foo"], true, 2);
+    },
+  });
+
+  // (4) Group "a.com" and name "foo" should no longer be cached.
+  getCachedOK(["a.com", "foo"], false);
+
+  // (5) Call getByDomainAndName.
+  let fetchedPref;
+  let getPromise = new Promise(resolve =>
+    cps.getByDomainAndName("a.com", "foo", null, {
+      handleResult(pref) {
+        fetchedPref = pref;
+      },
+      handleCompletion() {
+        // (7) Finally, this callback should be called after set's above.
+        Assert.ok(!!fetchedPref);
+        Assert.equal(fetchedPref.value, 2);
+        resolve();
+      },
+    })
+  );
+
+  await getPromise;
+  await reset();
+});
+
+add_task(async function get_nameOnly() {
+  await set("a.com", "foo", 1);
+  await set("a.com", "bar", 2);
+  await set("b.com", "foo", 3);
+  await setGlobal("foo", 4);
+
+  await getOKEx(
+    "getByName",
+    ["foo", undefined],
+    [
+      { domain: "a.com", name: "foo", value: 1 },
+      { domain: "b.com", name: "foo", value: 3 },
+      { domain: null, name: "foo", value: 4 },
+    ]
+  );
+
+  let context = privateLoadContext;
+  await set("b.com", "foo", 5, context);
+
+  await getOKEx(
+    "getByName",
+    ["foo", context],
+    [
+      { domain: "a.com", name: "foo", value: 1 },
+      { domain: null, name: "foo", value: 4 },
+      { domain: "b.com", name: "foo", value: 5 },
+    ]
+  );
+  await reset();
+});
+
+add_task(async function setSetsCurrentDate() {
+  // Because Date.now() is not guaranteed to be monotonically increasing
+  // we just do here rough sanity check with one minute tolerance.
+  const MINUTE = 60 * 1000;
+  let now = Date.now();
+  let start = now - MINUTE;
+  let end = now + MINUTE;
+  await set("a.com", "foo", 1);
+  let timestamp = await getDate("a.com", "foo");
+  Assert.lessOrEqual(
+    start,
+    timestamp,
+    "Timestamp is not too early (" + start + "<=" + timestamp + ")."
+  );
+  Assert.lessOrEqual(
+    timestamp,
+    end,
+    "Timestamp is not too late (" + timestamp + "<=" + end + ")."
+  );
+  await reset();
+});
+
+add_task(async function maxLength() {
+  const MAX_LENGTH = Ci.nsIContentPrefService2.GROUP_NAME_MAX_LENGTH;
+  const LONG_DATA_URL = `data:,${new Array(MAX_LENGTH).fill("x").join("")}`;
+  await set(LONG_DATA_URL, "foo", 1);
+  await getOK(
+    [LONG_DATA_URL, "foo"],
+    1,
+    LONG_DATA_URL.substring(0, MAX_LENGTH - 1)
+  );
+});
diff --git a/toolkit/components/contentprefs/tests/unit_cps2/xpcshell.toml b/toolkit/components/contentprefs/tests/unit_cps2/xpcshell.toml
new file mode 100644
index 0000000000..2b679c16f9
--- /dev/null
+++ b/toolkit/components/contentprefs/tests/unit_cps2/xpcshell.toml
@@ -0,0 +1,32 @@
+[DEFAULT]
+head = "head.js"
+skip-if = ["os == 'android'"]
+support-files = ["AsyncRunner.sys.mjs"]
+
+["test_extractDomain.js"]
+
+["test_getCached.js"]
+
+["test_getCachedSubdomains.js"]
+
+["test_getSubdomains.js"]
+
+["test_migrationToSchema4.js"]
+
+["test_migrationToSchema5.js"]
+
+["test_migrationToSchema6.js"]
+
+["test_observers.js"]
+
+["test_remove.js"]
+
+["test_removeAllDomains.js"]
+
+["test_removeAllDomainsSince.js"]
+
+["test_removeByDomain.js"]
+
+["test_removeByName.js"]
+
+["test_setGet.js"]