Adding upstream version 115.7.0esr.upstream/115.7.0esr

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

1 files changed, 1566 insertions, 0 deletions

diff --git a/toolkit/components/aboutprocesses/content/aboutProcesses.js b/toolkit/components/aboutprocesses/content/aboutProcesses.js
new file mode 100644
index 0000000000..1d94c52c1f
--- /dev/null
+++ b/toolkit/components/aboutprocesses/content/aboutProcesses.js
@@ -0,0 +1,1566 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*-*/
+/* vim: set ts=8 sts=2 et sw=2 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/. */
+
+"use strict";
+
+// Time in ms before we start changing the sort order again after receiving a
+// mousemove event.
+const TIME_BEFORE_SORTING_AGAIN = 5000;
+
+// How long we should wait between samples.
+const MINIMUM_INTERVAL_BETWEEN_SAMPLES_MS = 1000;
+
+// How often we should update
+const UPDATE_INTERVAL_MS = 2000;
+
+const NS_PER_US = 1000;
+const NS_PER_MS = 1000 * 1000;
+const NS_PER_S = 1000 * 1000 * 1000;
+const NS_PER_MIN = NS_PER_S * 60;
+const NS_PER_HOUR = NS_PER_MIN * 60;
+const NS_PER_DAY = NS_PER_HOUR * 24;
+
+const ONE_GIGA = 1024 * 1024 * 1024;
+const ONE_MEGA = 1024 * 1024;
+const ONE_KILO = 1024;
+
+const { XPCOMUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/XPCOMUtils.sys.mjs"
+);
+const { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+
+ChromeUtils.defineESModuleGetters(this, {
+  ContextualIdentityService:
+    "resource://gre/modules/ContextualIdentityService.sys.mjs",
+});
+
+XPCOMUtils.defineLazyGetter(this, "ProfilerPopupBackground", function () {
+  return ChromeUtils.import(
+    "resource://devtools/client/performance-new/shared/background.jsm.js"
+  );
+});
+
+const { WebExtensionPolicy } = Cu.getGlobalForObject(Services);
+
+const SHOW_THREADS = Services.prefs.getBoolPref(
+  "toolkit.aboutProcesses.showThreads"
+);
+const SHOW_ALL_SUBFRAMES = Services.prefs.getBoolPref(
+  "toolkit.aboutProcesses.showAllSubframes"
+);
+const SHOW_PROFILER_ICONS = Services.prefs.getBoolPref(
+  "toolkit.aboutProcesses.showProfilerIcons"
+);
+const PROFILE_DURATION = Math.max(
+  1,
+  Services.prefs.getIntPref("toolkit.aboutProcesses.profileDuration")
+);
+
+/**
+ * For the time being, Fluent doesn't support duration or memory formats, so we need
+ * to fetch units from Fluent. To avoid re-fetching at each update, we prefetch these
+ * units during initialization, asynchronously, and keep them.
+ *
+ * @type {
+ *   duration: { ns: String, us: String, ms: String, s: String, m: String, h: String, d: String },
+ *   memory: { B: String, KB: String, MB: String, GB: String, TB: String, PB: String, EB: String }
+ * }.
+ */
+let gLocalizedUnits;
+
+let tabFinder = {
+  update() {
+    this._map = new Map();
+    for (let win of Services.wm.getEnumerator("navigator:browser")) {
+      let tabbrowser = win.gBrowser;
+      for (let browser of tabbrowser.browsers) {
+        let id = browser.outerWindowID; // May be `null` if the browser isn't loaded yet
+        if (id != null) {
+          this._map.set(id, browser);
+        }
+      }
+      if (tabbrowser.preloadedBrowser) {
+        let browser = tabbrowser.preloadedBrowser;
+        if (browser.outerWindowID) {
+          this._map.set(browser.outerWindowID, browser);
+        }
+      }
+    }
+  },
+
+  /**
+   * Find the <xul:tab> for a window id.
+   *
+   * This is useful e.g. for reloading or closing tabs.
+   *
+   * @return null If the xul:tab could not be found, e.g. if the
+   * windowId is that of a chrome window.
+   * @return {{tabbrowser: <xul:tabbrowser>, tab: <xul.tab>}} The
+   * tabbrowser and tab if the latter could be found.
+   */
+  get(id) {
+    let browser = this._map.get(id);
+    if (!browser) {
+      return null;
+    }
+    let tabbrowser = browser.getTabBrowser();
+    if (!tabbrowser) {
+      return {
+        tabbrowser: null,
+        tab: {
+          getAttribute() {
+            return "";
+          },
+          linkedBrowser: browser,
+        },
+      };
+    }
+    return { tabbrowser, tab: tabbrowser.getTabForBrowser(browser) };
+  },
+};
+
+/**
+ * Utilities for dealing with state
+ */
+var State = {
+  // Store the previous and current samples so they can be compared.
+  _previous: null,
+  _latest: null,
+
+  async _promiseSnapshot() {
+    let date = Cu.now();
+    let main = await ChromeUtils.requestProcInfo();
+    main.date = date;
+
+    let processes = new Map();
+    processes.set(main.pid, main);
+    for (let child of main.children) {
+      child.date = date;
+      processes.set(child.pid, child);
+    }
+
+    return { processes, date };
+  },
+
+  /**
+   * Update the internal state.
+   *
+   * @return {Promise}
+   */
+  async update(force = false) {
+    if (
+      force ||
+      !this._latest ||
+      Cu.now() - this._latest.date > MINIMUM_INTERVAL_BETWEEN_SAMPLES_MS
+    ) {
+      // Replacing this._previous before we are done awaiting
+      // this._promiseSnapshot can cause this._previous and this._latest to be
+      // equal for a short amount of time, which can cause test failures when
+      // a forced update of the display is triggered in the meantime.
+      let newSnapshot = await this._promiseSnapshot();
+      this._previous = this._latest;
+      this._latest = newSnapshot;
+    }
+  },
+
+  _getThreadDelta(cur, prev, deltaT) {
+    let result = {
+      tid: cur.tid,
+      name: cur.name || `(${cur.tid})`,
+      // Total amount of CPU used, in ns.
+      totalCpu: cur.cpuTime,
+      slopeCpu: null,
+      active: null,
+    };
+    if (!deltaT) {
+      return result;
+    }
+    result.slopeCpu = (result.totalCpu - (prev ? prev.cpuTime : 0)) / deltaT;
+    result.active =
+      !!result.slopeCpu || cur.cpuCycleCount > (prev ? prev.cpuCycleCount : 0);
+    return result;
+  },
+
+  _getDOMWindows(process) {
+    if (!process.windows) {
+      return [];
+    }
+    if (!process.type == "extensions") {
+      return [];
+    }
+    let windows = process.windows.map(win => {
+      let tab = tabFinder.get(win.outerWindowId);
+      let addon =
+        process.type == "extension"
+          ? WebExtensionPolicy.getByURI(win.documentURI)
+          : null;
+      let displayRank;
+      if (tab) {
+        displayRank = 1;
+      } else if (win.isProcessRoot) {
+        displayRank = 2;
+      } else if (win.documentTitle) {
+        displayRank = 3;
+      } else {
+        displayRank = 4;
+      }
+      return {
+        outerWindowId: win.outerWindowId,
+        documentURI: win.documentURI,
+        documentTitle: win.documentTitle,
+        isProcessRoot: win.isProcessRoot,
+        isInProcess: win.isInProcess,
+        tab,
+        addon,
+        // The number of instances we have collapsed.
+        count: 1,
+        // A rank used to quickly sort windows.
+        displayRank,
+      };
+    });
+
+    // We keep all tabs and addons but we collapse subframes that have the same host.
+
+    // A map from host -> subframe.
+    let collapsible = new Map();
+    let result = [];
+    for (let win of windows) {
+      if (win.tab || win.addon) {
+        result.push(win);
+        continue;
+      }
+      let prev = collapsible.get(win.documentURI.prePath);
+      if (prev) {
+        prev.count += 1;
+      } else {
+        collapsible.set(win.documentURI.prePath, win);
+        result.push(win);
+      }
+    }
+    return result;
+  },
+
+  /**
+   * Compute the delta between two process snapshots.
+   *
+   * @param {ProcessSnapshot} cur
+   * @param {ProcessSnapshot?} prev
+   */
+  _getProcessDelta(cur, prev) {
+    let windows = this._getDOMWindows(cur);
+    let result = {
+      pid: cur.pid,
+      childID: cur.childID,
+      totalRamSize: cur.memory,
+      deltaRamSize: null,
+      totalCpu: cur.cpuTime,
+      slopeCpu: null,
+      active: null,
+      type: cur.type,
+      origin: cur.origin || "",
+      threads: null,
+      displayRank: Control._getDisplayGroupRank(cur, windows),
+      windows,
+      utilityActors: cur.utilityActors,
+      // If this process has an unambiguous title, store it here.
+      title: null,
+    };
+    // Attempt to determine a title for this process.
+    let titles = [
+      ...new Set(
+        result.windows
+          .filter(win => win.documentTitle)
+          .map(win => win.documentTitle)
+      ),
+    ];
+    if (titles.length == 1) {
+      result.title = titles[0];
+    }
+    if (!prev) {
+      if (SHOW_THREADS) {
+        result.threads = cur.threads.map(data => this._getThreadDelta(data));
+      }
+      return result;
+    }
+    if (prev.pid != cur.pid) {
+      throw new Error("Assertion failed: A process cannot change pid.");
+    }
+    let deltaT = (cur.date - prev.date) * NS_PER_MS;
+    let threads = null;
+    if (SHOW_THREADS) {
+      let prevThreads = new Map();
+      for (let thread of prev.threads) {
+        prevThreads.set(thread.tid, thread);
+      }
+      threads = cur.threads.map(curThread =>
+        this._getThreadDelta(curThread, prevThreads.get(curThread.tid), deltaT)
+      );
+    }
+    result.deltaRamSize = cur.memory - prev.memory;
+    result.slopeCpu = (cur.cpuTime - prev.cpuTime) / deltaT;
+    result.active = !!result.slopeCpu || cur.cpuCycleCount > prev.cpuCycleCount;
+    result.threads = threads;
+    return result;
+  },
+
+  getCounters() {
+    tabFinder.update();
+
+    let counters = [];
+
+    for (let cur of this._latest.processes.values()) {
+      let prev = this._previous?.processes.get(cur.pid);
+      counters.push(this._getProcessDelta(cur, prev));
+    }
+
+    return counters;
+  },
+};
+
+var View = {
+  // Processes, tabs and subframes that we killed during the previous iteration.
+  // Array<{pid:Number} | {windowId:Number}>
+  _killedRecently: [],
+  commit() {
+    this._killedRecently.length = 0;
+    let tbody = document.getElementById("process-tbody");
+
+    let insertPoint = tbody.firstChild;
+    let nextRow;
+    while ((nextRow = this._orderedRows.shift())) {
+      if (insertPoint && insertPoint === nextRow) {
+        insertPoint = insertPoint.nextSibling;
+      } else {
+        tbody.insertBefore(nextRow, insertPoint);
+      }
+    }
+
+    if (insertPoint) {
+      while ((nextRow = insertPoint.nextSibling)) {
+        this._removeRow(nextRow);
+      }
+      this._removeRow(insertPoint);
+    }
+  },
+  // If we are not going to display the updated list of rows, drop references
+  // to rows that haven't been inserted in the DOM tree.
+  discardUpdate() {
+    for (let row of this._orderedRows) {
+      if (!row.parentNode) {
+        this._rowsById.delete(row.rowId);
+      }
+    }
+    this._orderedRows = [];
+  },
+  insertAfterRow(row) {
+    let tbody = row.parentNode;
+    let nextRow;
+    while ((nextRow = this._orderedRows.pop())) {
+      tbody.insertBefore(nextRow, row.nextSibling);
+    }
+  },
+
+  _rowsById: new Map(),
+  _removeRow(row) {
+    this._rowsById.delete(row.rowId);
+
+    row.remove();
+  },
+  _getOrCreateRow(rowId, cellCount) {
+    let row = this._rowsById.get(rowId);
+    if (!row) {
+      row = document.createElement("tr");
+      while (cellCount--) {
+        row.appendChild(document.createElement("td"));
+      }
+      row.rowId = rowId;
+      this._rowsById.set(rowId, row);
+    }
+    this._orderedRows.push(row);
+    return row;
+  },
+
+  displayCpu(data, cpuCell, maxSlopeCpu) {
+    // Put a value < 0% when we really don't want to see a bar as
+    // otherwise it sometimes appears due to rounding errors when we
+    // don't have an integer number of pixels.
+    let barWidth = -0.5;
+    if (data.slopeCpu == null) {
+      this._fillCell(cpuCell, {
+        fluentName: "about-processes-cpu-user-and-kernel-not-ready",
+        classes: ["cpu"],
+      });
+    } else {
+      let { duration, unit } = this._getDuration(data.totalCpu);
+      if (data.totalCpu == 0) {
+        // A thread having used exactly 0ns of CPU time is not possible.
+        // When we get 0 it means the thread used less than the precision of
+        // the measurement, and it makes more sense to show '0ms' than '0ns'.
+        // This is useful on Linux where the minimum non-zero CPU time value
+        // for threads of child processes is 10ms, and on Windows ARM64 where
+        // the minimum non-zero value is 16ms.
+        unit = "ms";
+      }
+      let localizedUnit = gLocalizedUnits.duration[unit];
+      if (data.slopeCpu == 0) {
+        let fluentName = data.active
+          ? "about-processes-cpu-almost-idle"
+          : "about-processes-cpu-fully-idle";
+        this._fillCell(cpuCell, {
+          fluentName,
+          fluentArgs: {
+            total: duration,
+            unit: localizedUnit,
+          },
+          classes: ["cpu"],
+        });
+      } else {
+        this._fillCell(cpuCell, {
+          fluentName: "about-processes-cpu",
+          fluentArgs: {
+            percent: data.slopeCpu,
+            total: duration,
+            unit: localizedUnit,
+          },
+          classes: ["cpu"],
+        });
+
+        let cpuPercent = data.slopeCpu * 100;
+        if (maxSlopeCpu > 1) {
+          cpuPercent /= maxSlopeCpu;
+        }
+        // Ensure we always have a visible bar for non-0 values.
+        barWidth = Math.max(0.5, cpuPercent);
+      }
+    }
+    cpuCell.style.setProperty("--bar-width", barWidth);
+  },
+
+  /**
+   * Display a row showing a single process (without its threads).
+   *
+   * @param {ProcessDelta} data The data to display.
+   * @param {Number} maxSlopeCpu The largest slopeCpu value.
+   * @return {DOMElement} The row displaying the process.
+   */
+  displayProcessRow(data, maxSlopeCpu) {
+    const cellCount = 4;
+    let rowId = "p:" + data.pid;
+    let row = this._getOrCreateRow(rowId, cellCount);
+    row.process = data;
+    {
+      let classNames = "process";
+      if (data.isHung) {
+        classNames += " hung";
+      }
+      row.className = classNames;
+    }
+
+    // Column: Name
+    let nameCell = row.firstChild;
+    {
+      let classNames = [];
+      let fluentName;
+      let fluentArgs = {
+        pid: "" + data.pid, // Make sure that this number is not localized
+      };
+      switch (data.type) {
+        case "web":
+          fluentName = "about-processes-web-process";
+          break;
+        case "webIsolated":
+          fluentName = "about-processes-web-isolated-process";
+          fluentArgs.origin = data.origin;
+          break;
+        case "webServiceWorker":
+          fluentName = "about-processes-web-serviceworker";
+          fluentArgs.origin = data.origin;
+          break;
+        case "file":
+          fluentName = "about-processes-file-process";
+          break;
+        case "extension":
+          fluentName = "about-processes-extension-process";
+          classNames = ["extensions"];
+          break;
+        case "privilegedabout":
+          fluentName = "about-processes-privilegedabout-process";
+          break;
+        case "privilegedmozilla":
+          fluentName = "about-processes-privilegedmozilla-process";
+          break;
+        case "withCoopCoep":
+          fluentName = "about-processes-with-coop-coep-process";
+          fluentArgs.origin = data.origin;
+          break;
+        case "browser":
+          fluentName = "about-processes-browser-process";
+          break;
+        case "plugin":
+          fluentName = "about-processes-plugin-process";
+          break;
+        case "gmpPlugin":
+          fluentName = "about-processes-gmp-plugin-process";
+          break;
+        case "gpu":
+          fluentName = "about-processes-gpu-process";
+          break;
+        case "vr":
+          fluentName = "about-processes-vr-process";
+          break;
+        case "rdd":
+          fluentName = "about-processes-rdd-process";
+          break;
+        case "socket":
+          fluentName = "about-processes-socket-process";
+          break;
+        case "remoteSandboxBroker":
+          fluentName = "about-processes-remote-sandbox-broker-process";
+          break;
+        case "forkServer":
+          fluentName = "about-processes-fork-server-process";
+          break;
+        case "preallocated":
+          fluentName = "about-processes-preallocated-process";
+          break;
+        case "utility":
+          fluentName = "about-processes-utility-process";
+          break;
+        // The following are probably not going to show up for users
+        // but let's handle the case anyway to avoid heisenoranges
+        // during tests in case of a leftover process from a previous
+        // test.
+        default:
+          fluentName = "about-processes-unknown-process";
+          fluentArgs.type = data.type;
+          break;
+      }
+
+      // Show container names instead of raw origin attribute suffixes.
+      if (fluentArgs.origin?.includes("^")) {
+        let origin = fluentArgs.origin;
+        let privateBrowsingId, userContextId;
+        try {
+          ({ privateBrowsingId, userContextId } =
+            ChromeUtils.createOriginAttributesFromOrigin(origin));
+          fluentArgs.origin = origin.slice(0, origin.indexOf("^"));
+        } catch (e) {
+          // createOriginAttributesFromOrigin can throw NS_ERROR_FAILURE for incorrect origin strings.
+        }
+        if (userContextId) {
+          let identityLabel =
+            ContextualIdentityService.getUserContextLabel(userContextId);
+          if (identityLabel) {
+            fluentArgs.origin += ` — ${identityLabel}`;
+          }
+        }
+        if (privateBrowsingId) {
+          fluentName += "-private";
+        }
+      }
+
+      let processNameElement = nameCell;
+      if (SHOW_PROFILER_ICONS) {
+        if (!nameCell.firstChild) {
+          processNameElement = document.createElement("span");
+          nameCell.appendChild(processNameElement);
+
+          let profilerIcon = document.createElement("span");
+          profilerIcon.className = "profiler-icon";
+          document.l10n.setAttributes(
+            profilerIcon,
+            "about-processes-profile-process",
+            { duration: PROFILE_DURATION }
+          );
+          nameCell.appendChild(profilerIcon);
+        } else {
+          processNameElement = nameCell.firstChild;
+        }
+      }
+      document.l10n.setAttributes(processNameElement, fluentName, fluentArgs);
+      nameCell.className = ["type", "favicon", ...classNames].join(" ");
+      nameCell.setAttribute("id", data.pid + "-label");
+
+      let image;
+      switch (data.type) {
+        case "browser":
+        case "privilegedabout":
+          image = "chrome://branding/content/icon32.png";
+          break;
+        case "extension":
+          image = "chrome://mozapps/skin/extensions/extension.svg";
+          break;
+        default:
+          // If all favicons match, pick the shared favicon.
+          // Otherwise, pick a default icon.
+          // If some tabs have no favicon, we ignore them.
+          for (let win of data.windows || []) {
+            if (!win.tab) {
+              continue;
+            }
+            let favicon = win.tab.tab.getAttribute("image");
+            if (!favicon) {
+              // No favicon here, let's ignore the tab.
+            } else if (!image) {
+              // Let's pick a first favicon.
+              // We'll remove it later if we find conflicting favicons.
+              image = favicon;
+            } else if (image == favicon) {
+              // So far, no conflict, keep the favicon.
+            } else {
+              // Conflicting favicons, fallback to default.
+              image = null;
+              break;
+            }
+          }
+          if (!image) {
+            image = "chrome://global/skin/icons/link.svg";
+          }
+      }
+      nameCell.style.backgroundImage = `url('${image}')`;
+    }
+
+    // Column: Memory
+    let memoryCell = nameCell.nextSibling;
+    {
+      let formattedTotal = this._formatMemory(data.totalRamSize);
+      if (data.deltaRamSize) {
+        let formattedDelta = this._formatMemory(data.deltaRamSize);
+        this._fillCell(memoryCell, {
+          fluentName: "about-processes-total-memory-size-changed",
+          fluentArgs: {
+            total: formattedTotal.amount,
+            totalUnit: gLocalizedUnits.memory[formattedTotal.unit],
+            delta: Math.abs(formattedDelta.amount),
+            deltaUnit: gLocalizedUnits.memory[formattedDelta.unit],
+            deltaSign: data.deltaRamSize > 0 ? "+" : "-",
+          },
+          classes: ["memory"],
+        });
+      } else {
+        this._fillCell(memoryCell, {
+          fluentName: "about-processes-total-memory-size-no-change",
+          fluentArgs: {
+            total: formattedTotal.amount,
+            totalUnit: gLocalizedUnits.memory[formattedTotal.unit],
+          },
+          classes: ["memory"],
+        });
+      }
+    }
+
+    // Column: CPU
+    let cpuCell = memoryCell.nextSibling;
+    this.displayCpu(data, cpuCell, maxSlopeCpu);
+
+    // Column: Kill button – but not for all processes.
+    let killButton = cpuCell.nextSibling;
+    killButton.className = "action-icon";
+
+    if (data.type.startsWith("web")) {
+      // This type of process can be killed.
+      if (this._killedRecently.some(kill => kill.pid && kill.pid == data.pid)) {
+        // We're racing between the "kill" action and the visual refresh.
+        // In a few cases, we could end up with the visual refresh showing
+        // a process as un-killed while we actually just killed it.
+        //
+        // We still want to display the process in case something actually
+        // went bad and the user needs the information to realize this.
+        // But we also want to make it visible that the process is being
+        // killed.
+        row.classList.add("killed");
+      } else {
+        // Otherwise, let's display the kill button.
+        killButton.classList.add("close-icon");
+        document.l10n.setAttributes(
+          killButton,
+          "about-processes-shutdown-process"
+        );
+      }
+    }
+
+    return row;
+  },
+
+  /**
+   * Display a thread summary row with the thread count and a twisty to
+   * open/close the list.
+   *
+   * @param {ProcessDelta} data The data to display.
+   * @return {boolean} Whether the full thread list should be displayed.
+   */
+  displayThreadSummaryRow(data) {
+    const cellCount = 2;
+    let rowId = "ts:" + data.pid;
+    let row = this._getOrCreateRow(rowId, cellCount);
+    row.process = data;
+    row.className = "thread-summary";
+    let isOpen = false;
+
+    // Column: Name
+    let nameCell = row.firstChild;
+    let threads = data.threads;
+    let activeThreads = new Map();
+    let activeThreadCount = 0;
+    for (let t of data.threads) {
+      if (!t.active) {
+        continue;
+      }
+      ++activeThreadCount;
+      let name = t.name.replace(/ ?#[0-9]+$/, "");
+      if (!activeThreads.has(name)) {
+        activeThreads.set(name, { name, slopeCpu: t.slopeCpu, count: 1 });
+      } else {
+        let thread = activeThreads.get(name);
+        thread.count++;
+        thread.slopeCpu += t.slopeCpu;
+      }
+    }
+    let fluentName, fluentArgs;
+    if (activeThreadCount) {
+      let percentFormatter = new Intl.NumberFormat(undefined, {
+        style: "percent",
+        minimumSignificantDigits: 1,
+      });
+
+      let threadList = Array.from(activeThreads.values());
+      threadList.sort((t1, t2) => t2.slopeCpu - t1.slopeCpu);
+
+      fluentName = "about-processes-active-threads";
+      fluentArgs = {
+        number: threads.length,
+        active: activeThreadCount,
+        list: new Intl.ListFormat(undefined, { style: "narrow" }).format(
+          threadList.map(t => {
+            let name = t.count > 1 ? `${t.count} × ${t.name}` : t.name;
+            let percent = Math.round(t.slopeCpu * 1000) / 1000;
+            if (percent) {
+              return `${name} ${percentFormatter.format(percent)}`;
+            }
+            return name;
+          })
+        ),
+      };
+    } else {
+      fluentName = "about-processes-inactive-threads";
+      fluentArgs = {
+        number: threads.length,
+      };
+    }
+
+    let span;
+    if (!nameCell.firstChild) {
+      nameCell.className = "name indent";
+      // Create the nodes:
+      let imgBtn = document.createElement("span");
+      // Provide markup for an accessible disclosure button:
+      imgBtn.className = "twisty";
+      imgBtn.setAttribute("role", "button");
+      imgBtn.setAttribute("tabindex", "0");
+      // Label to include both summary and details texts
+      imgBtn.setAttribute("aria-labelledby", `${data.pid}-label ${rowId}`);
+      if (!imgBtn.hasAttribute("aria-expanded")) {
+        imgBtn.setAttribute("aria-expanded", "false");
+      }
+      nameCell.appendChild(imgBtn);
+
+      span = document.createElement("span");
+      span.setAttribute("id", rowId);
+      nameCell.appendChild(span);
+    } else {
+      // The only thing that can change is the thread count.
+      let imgBtn = nameCell.firstChild;
+      isOpen = imgBtn.classList.contains("open");
+      span = imgBtn.nextSibling;
+    }
+    document.l10n.setAttributes(span, fluentName, fluentArgs);
+
+    // Column: action
+    let actionCell = nameCell.nextSibling;
+    actionCell.className = "action-icon";
+
+    return isOpen;
+  },
+
+  displayDOMWindowRow(data, parent) {
+    const cellCount = 2;
+    let rowId = "w:" + data.outerWindowId;
+    let row = this._getOrCreateRow(rowId, cellCount);
+    row.win = data;
+    row.className = "window";
+
+    // Column: name
+    let nameCell = row.firstChild;
+    let tab = tabFinder.get(data.outerWindowId);
+    let fluentName;
+    let fluentArgs = {};
+    let className;
+    if (tab && tab.tabbrowser) {
+      fluentName = "about-processes-tab-name";
+      fluentArgs.name = tab.tab.label;
+      className = "tab";
+    } else if (tab) {
+      fluentName = "about-processes-preloaded-tab";
+      className = "preloaded-tab";
+    } else if (data.count == 1) {
+      fluentName = "about-processes-frame-name-one";
+      fluentArgs.url = data.documentURI.spec;
+      className = "frame-one";
+    } else {
+      fluentName = "about-processes-frame-name-many";
+      fluentArgs.number = data.count;
+      fluentArgs.shortUrl =
+        data.documentURI.scheme == "about"
+          ? data.documentURI.spec
+          : data.documentURI.prePath;
+      className = "frame-many";
+    }
+    this._fillCell(nameCell, {
+      fluentName,
+      fluentArgs,
+      classes: ["name", "indent", "favicon", className],
+    });
+    let image = tab?.tab.getAttribute("image");
+    if (image) {
+      nameCell.style.backgroundImage = `url('${image}')`;
+    }
+
+    // Column: action
+    let killButton = nameCell.nextSibling;
+    killButton.className = "action-icon";
+
+    if (data.tab && data.tab.tabbrowser) {
+      // A tab. We want to be able to close it.
+      if (
+        this._killedRecently.some(
+          kill => kill.windowId && kill.windowId == data.outerWindowId
+        )
+      ) {
+        // We're racing between the "kill" action and the visual refresh.
+        // In a few cases, we could end up with the visual refresh showing
+        // a window as un-killed while we actually just killed it.
+        //
+        // We still want to display the window in case something actually
+        // went bad and the user needs the information to realize this.
+        // But we also want to make it visible that the window is being
+        // killed.
+        row.classList.add("killed");
+      } else {
+        // Otherwise, let's display the kill button.
+        killButton.classList.add("close-icon");
+        document.l10n.setAttributes(killButton, "about-processes-shutdown-tab");
+      }
+    }
+  },
+
+  utilityActorNameToFluentName(actorName) {
+    let fluentName;
+    switch (actorName) {
+      case "audioDecoder_Generic":
+        fluentName = "about-processes-utility-actor-audio-decoder-generic";
+        break;
+
+      case "audioDecoder_AppleMedia":
+        fluentName = "about-processes-utility-actor-audio-decoder-applemedia";
+        break;
+
+      case "audioDecoder_WMF":
+        fluentName = "about-processes-utility-actor-audio-decoder-wmf";
+        break;
+
+      case "mfMediaEngineCDM":
+        fluentName = "about-processes-utility-actor-mf-media-engine";
+        break;
+
+      case "jSOracle":
+        fluentName = "about-processes-utility-actor-js-oracle";
+        break;
+
+      case "windowsUtils":
+        fluentName = "about-processes-utility-actor-windows-utils";
+        break;
+
+      default:
+        fluentName = "about-processes-utility-actor-unknown";
+        break;
+    }
+    return fluentName;
+  },
+
+  displayUtilityActorRow(data, parent) {
+    const cellCount = 2;
+    // The actor name is expected to be unique within a given utility process.
+    let rowId = "u:" + parent.pid + data.actorName;
+    let row = this._getOrCreateRow(rowId, cellCount);
+    row.actor = data;
+    row.className = "actor";
+
+    // Column: name
+    let nameCell = row.firstChild;
+    let fluentName = this.utilityActorNameToFluentName(data.actorName);
+    let fluentArgs = {};
+    this._fillCell(nameCell, {
+      fluentName,
+      fluentArgs,
+      classes: ["name", "indent", "favicon"],
+    });
+  },
+
+  /**
+   * Display a row showing a single thread.
+   *
+   * @param {ThreadDelta} data The data to display.
+   * @param {Number} maxSlopeCpu The largest slopeCpu value.
+   */
+  displayThreadRow(data, maxSlopeCpu) {
+    const cellCount = 3;
+    let rowId = "t:" + data.tid;
+    let row = this._getOrCreateRow(rowId, cellCount);
+    row.thread = data;
+    row.className = "thread";
+
+    // Column: name
+    let nameCell = row.firstChild;
+    this._fillCell(nameCell, {
+      fluentName: "about-processes-thread-name-and-id",
+      fluentArgs: {
+        name: data.name,
+        tid: "" + data.tid /* Make sure that this number is not localized */,
+      },
+      classes: ["name", "double_indent"],
+    });
+
+    // Column: CPU
+    this.displayCpu(data, nameCell.nextSibling, maxSlopeCpu);
+
+    // Third column (Buttons) is empty, nothing to do.
+  },
+
+  _orderedRows: [],
+  _fillCell(elt, { classes, fluentName, fluentArgs }) {
+    document.l10n.setAttributes(elt, fluentName, fluentArgs);
+    elt.className = classes.join(" ");
+  },
+
+  _getDuration(rawDurationNS) {
+    if (rawDurationNS <= NS_PER_US) {
+      return { duration: rawDurationNS, unit: "ns" };
+    }
+    if (rawDurationNS <= NS_PER_MS) {
+      return { duration: rawDurationNS / NS_PER_US, unit: "us" };
+    }
+    if (rawDurationNS <= NS_PER_S) {
+      return { duration: rawDurationNS / NS_PER_MS, unit: "ms" };
+    }
+    if (rawDurationNS <= NS_PER_MIN) {
+      return { duration: rawDurationNS / NS_PER_S, unit: "s" };
+    }
+    if (rawDurationNS <= NS_PER_HOUR) {
+      return { duration: rawDurationNS / NS_PER_MIN, unit: "m" };
+    }
+    if (rawDurationNS <= NS_PER_DAY) {
+      return { duration: rawDurationNS / NS_PER_HOUR, unit: "h" };
+    }
+    return { duration: rawDurationNS / NS_PER_DAY, unit: "d" };
+  },
+
+  /**
+   * Format a value representing an amount of memory.
+   *
+   * As a special case, we also handle `null`, which represents the case in which we do
+   * not have sufficient information to compute an amount of memory.
+   *
+   * @param {Number?} value The value to format. Must be either `null` or a non-negative number.
+   * @return { {unit: "GB" | "MB" | "KB" | B" | "?"}, amount: Number } The formated amount and its
+   *  unit, which may be used for e.g. additional CSS formating.
+   */
+  _formatMemory(value) {
+    if (value == null) {
+      return { unit: "?", amount: 0 };
+    }
+    if (typeof value != "number") {
+      throw new Error(`Invalid memory value ${value}`);
+    }
+    let abs = Math.abs(value);
+    if (abs >= ONE_GIGA) {
+      return {
+        unit: "GB",
+        amount: value / ONE_GIGA,
+      };
+    }
+    if (abs >= ONE_MEGA) {
+      return {
+        unit: "MB",
+        amount: value / ONE_MEGA,
+      };
+    }
+    if (abs >= ONE_KILO) {
+      return {
+        unit: "KB",
+        amount: value / ONE_KILO,
+      };
+    }
+    return {
+      unit: "B",
+      amount: value,
+    };
+  },
+};
+
+var Control = {
+  // The set of all processes reported as "hung" by the process hang monitor.
+  //
+  // type: Set<ChildID>
+  _hungItems: new Set(),
+  _sortColumn: null,
+  _sortAscendent: true,
+  _removeSubtree(row) {
+    let sibling = row.nextSibling;
+    while (sibling && !sibling.classList.contains("process")) {
+      let next = sibling.nextSibling;
+      if (sibling.classList.contains("thread")) {
+        View._removeRow(sibling);
+      }
+      sibling = next;
+    }
+  },
+  init() {
+    this._initHangReports();
+
+    // Start prefetching units.
+    this._promisePrefetchedUnits = (async function () {
+      let [ns, us, ms, s, m, h, d, B, KB, MB, GB, TB, PB, EB] =
+        await document.l10n.formatValues([
+          { id: "duration-unit-ns" },
+          { id: "duration-unit-us" },
+          { id: "duration-unit-ms" },
+          { id: "duration-unit-s" },
+          { id: "duration-unit-m" },
+          { id: "duration-unit-h" },
+          { id: "duration-unit-d" },
+          { id: "memory-unit-B" },
+          { id: "memory-unit-KB" },
+          { id: "memory-unit-MB" },
+          { id: "memory-unit-GB" },
+          { id: "memory-unit-TB" },
+          { id: "memory-unit-PB" },
+          { id: "memory-unit-EB" },
+        ]);
+      return {
+        duration: { ns, us, ms, s, m, h, d },
+        memory: { B, KB, MB, GB, TB, PB, EB },
+      };
+    })();
+
+    let tbody = document.getElementById("process-tbody");
+
+    // Single click:
+    // - show or hide the contents of a twisty;
+    // - close a process;
+    // - profile a process;
+    // - change selection.
+    tbody.addEventListener("click", event => {
+      this._updateLastMouseEvent();
+
+      this._handleActivate(event.target);
+    });
+
+    // Enter or Space keypress:
+    // - show or hide the contents of a twisty;
+    // - close a process;
+    // - profile a process;
+    // - change selection.
+    tbody.addEventListener("keypress", event => {
+      // Handle showing or hiding subitems of a row, when keyboard is used.
+      if (event.key === "Enter" || event.key === " ") {
+        this._handleActivate(event.target);
+      }
+    });
+
+    // Double click:
+    // - navigate to tab;
+    // - navigate to about:addons.
+    tbody.addEventListener("dblclick", event => {
+      this._updateLastMouseEvent();
+      event.stopPropagation();
+
+      // Bubble up the doubleclick manually.
+      for (
+        let target = event.target;
+        target && target.getAttribute("id") != "process-tbody";
+        target = target.parentNode
+      ) {
+        if (target.classList.contains("tab")) {
+          // We've clicked on a tab, navigate.
+          let { tab, tabbrowser } = target.parentNode.win.tab;
+          tabbrowser.selectedTab = tab;
+          tabbrowser.ownerGlobal.focus();
+          return;
+        }
+        if (target.classList.contains("extensions")) {
+          // We've clicked on the extensions process, open or reuse window.
+          let parentWin =
+            window.docShell.browsingContext.embedderElement.ownerGlobal;
+          parentWin.BrowserOpenAddonsMgr();
+          return;
+        }
+        // Otherwise, proceed.
+      }
+    });
+
+    tbody.addEventListener("mousemove", () => {
+      this._updateLastMouseEvent();
+    });
+
+    // Visibility change:
+    // - stop updating while the user isn't looking;
+    // - resume updating when the user returns.
+    window.addEventListener("visibilitychange", event => {
+      if (!document.hidden) {
+        this._updateDisplay(true);
+      }
+    });
+
+    document
+      .getElementById("process-thead")
+      .addEventListener("click", async event => {
+        if (!event.target.classList.contains("clickable")) {
+          return;
+        }
+        // Linux has conventions opposite to Windows and macOS on the direction of arrows
+        // when sorting.
+        const platformIsLinux = AppConstants.platform == "linux";
+        const ascArrow = platformIsLinux ? "arrow-up" : "arrow-down";
+        const descArrow = platformIsLinux ? "arrow-down" : "arrow-up";
+
+        if (this._sortColumn) {
+          const td = document.getElementById(this._sortColumn);
+          td.classList.remove(ascArrow, descArrow);
+        }
+
+        const columnId = event.target.id;
+        if (columnId == this._sortColumn) {
+          // Reverse sorting order.
+          this._sortAscendent = !this._sortAscendent;
+        } else {
+          this._sortColumn = columnId;
+          this._sortAscendent = true;
+        }
+
+        event.target.classList.toggle(ascArrow, this._sortAscendent);
+        event.target.classList.toggle(descArrow, !this._sortAscendent);
+
+        await this._updateDisplay(true);
+      });
+  },
+  _lastMouseEvent: 0,
+  _updateLastMouseEvent() {
+    this._lastMouseEvent = Date.now();
+  },
+  _initHangReports() {
+    const PROCESS_HANG_REPORT_NOTIFICATION = "process-hang-report";
+
+    // Receiving report of a hung child.
+    // Let's store if for our next update.
+    let hangReporter = report => {
+      report.QueryInterface(Ci.nsIHangReport);
+      this._hungItems.add(report.childID);
+    };
+    Services.obs.addObserver(hangReporter, PROCESS_HANG_REPORT_NOTIFICATION);
+
+    // Don't forget to unregister the reporter.
+    window.addEventListener(
+      "unload",
+      () => {
+        Services.obs.removeObserver(
+          hangReporter,
+          PROCESS_HANG_REPORT_NOTIFICATION
+        );
+      },
+      { once: true }
+    );
+  },
+  async update(force = false) {
+    await State.update(force);
+
+    if (document.hidden) {
+      return;
+    }
+
+    await this._updateDisplay(force);
+  },
+
+  // The force parameter can force a full update even when the mouse has been
+  // moved recently.
+  async _updateDisplay(force = false) {
+    let counters = State.getCounters();
+    if (this._promisePrefetchedUnits) {
+      gLocalizedUnits = await this._promisePrefetchedUnits;
+      this._promisePrefetchedUnits = null;
+    }
+
+    // We reset `_hungItems`, based on the assumption that the process hang
+    // monitor will inform us again before the next update. Since the process hang monitor
+    // pings its clients about once per second and we update about once per 2 seconds
+    // (or more if the mouse moves), we should be ok.
+    let hungItems = this._hungItems;
+    this._hungItems = new Set();
+
+    counters = this._sortProcesses(counters);
+
+    // Stored because it is used when opening the list of threads.
+    this._maxSlopeCpu = Math.max(...counters.map(process => process.slopeCpu));
+
+    let previousProcess = null;
+    for (let process of counters) {
+      this._sortDOMWindows(process.windows);
+
+      process.isHung = process.childID && hungItems.has(process.childID);
+
+      let processRow = View.displayProcessRow(process, this._maxSlopeCpu);
+
+      if (process.type != "extension") {
+        // We do not want to display extensions.
+        for (let win of process.windows) {
+          if (SHOW_ALL_SUBFRAMES || win.tab || win.isProcessRoot) {
+            View.displayDOMWindowRow(win, process);
+          }
+        }
+      }
+
+      if (process.type === "utility") {
+        for (let actor of process.utilityActors) {
+          View.displayUtilityActorRow(actor, process);
+        }
+      }
+
+      if (SHOW_THREADS) {
+        if (View.displayThreadSummaryRow(process)) {
+          this._showThreads(processRow, this._maxSlopeCpu);
+        }
+      }
+      if (
+        this._sortColumn == null &&
+        previousProcess &&
+        previousProcess.displayRank != process.displayRank
+      ) {
+        // Add a separation between successive categories of processes.
+        processRow.classList.add("separate-from-previous-process-group");
+      }
+      previousProcess = process;
+    }
+
+    if (
+      !force &&
+      Date.now() - this._lastMouseEvent < TIME_BEFORE_SORTING_AGAIN
+    ) {
+      // If there has been a recent mouse event, we don't want to reorder,
+      // add or remove rows so that the table content under the mouse pointer
+      // doesn't change when the user might be about to click to close a tab
+      // or kill a process.
+      // We didn't return earlier because updating CPU and memory values is
+      // still valuable.
+      View.discardUpdate();
+      return;
+    }
+
+    View.commit();
+
+    // Reset the selectedRow field if that row is no longer in the DOM
+    // to avoid keeping forever references to dead processes.
+    if (this.selectedRow && !this.selectedRow.parentNode) {
+      this.selectedRow = null;
+    }
+
+    // Used by tests to differentiate full updates from l10n updates.
+    document.dispatchEvent(new CustomEvent("AboutProcessesUpdated"));
+  },
+  _compareCpu(a, b) {
+    return (
+      b.slopeCpu - a.slopeCpu || b.active - a.active || b.totalCpu - a.totalCpu
+    );
+  },
+  _showThreads(row, maxSlopeCpu) {
+    let process = row.process;
+    this._sortThreads(process.threads);
+    for (let thread of process.threads) {
+      View.displayThreadRow(thread, maxSlopeCpu);
+    }
+  },
+  _sortThreads(threads) {
+    return threads.sort((a, b) => {
+      let order;
+      switch (this._sortColumn) {
+        case "column-name":
+          order = a.name.localeCompare(b.name) || a.tid - b.tid;
+          break;
+        case "column-cpu-total":
+          order = this._compareCpu(a, b);
+          break;
+        case "column-memory-resident":
+        case null:
+          order = a.tid - b.tid;
+          break;
+        default:
+          throw new Error("Unsupported order: " + this._sortColumn);
+      }
+      if (!this._sortAscendent) {
+        order = -order;
+      }
+      return order;
+    });
+  },
+  _sortProcesses(counters) {
+    return counters.sort((a, b) => {
+      let order;
+      switch (this._sortColumn) {
+        case "column-name":
+          order =
+            String(a.origin).localeCompare(b.origin) ||
+            String(a.type).localeCompare(b.type) ||
+            a.pid - b.pid;
+          break;
+        case "column-cpu-total":
+          order = this._compareCpu(a, b);
+          break;
+        case "column-memory-resident":
+          order = b.totalRamSize - a.totalRamSize;
+          break;
+        case null:
+          // Default order: classify processes by group.
+          order =
+            a.displayRank - b.displayRank ||
+            // Other processes are ordered by origin.
+            String(a.origin).localeCompare(b.origin);
+          break;
+        default:
+          throw new Error("Unsupported order: " + this._sortColumn);
+      }
+      if (!this._sortAscendent) {
+        order = -order;
+      }
+      return order;
+    });
+  },
+  _sortDOMWindows(windows) {
+    return windows.sort((a, b) => {
+      let order =
+        a.displayRank - b.displayRank ||
+        a.documentTitle.localeCompare(b.documentTitle) ||
+        a.documentURI.spec.localeCompare(b.documentURI.spec);
+      if (!this._sortAscendent) {
+        order = -order;
+      }
+      return order;
+    });
+  },
+
+  // Assign a display rank to a process.
+  //
+  // The `browser` process comes first (rank 0).
+  // Then come web tabs (rank 1).
+  // Then come web frames (rank 2).
+  // Then come special processes (minus preallocated) (rank 3).
+  // Then come preallocated processes (rank 4).
+  _getDisplayGroupRank(data, windows) {
+    const RANK_BROWSER = 0;
+    const RANK_WEB_TABS = 1;
+    const RANK_WEB_FRAMES = 2;
+    const RANK_UTILITY = 3;
+    const RANK_PREALLOCATED = 4;
+    let type = data.type;
+    switch (type) {
+      // Browser comes first.
+      case "browser":
+        return RANK_BROWSER;
+      // Web content comes next.
+      case "webIsolated":
+      case "webServiceWorker":
+      case "withCoopCoep": {
+        if (windows.some(w => w.tab)) {
+          return RANK_WEB_TABS;
+        }
+        return RANK_WEB_FRAMES;
+      }
+      // Preallocated processes come last.
+      case "preallocated":
+        return RANK_PREALLOCATED;
+      // "web" is special, as it could be one of:
+      // - web content currently loading/unloading/...
+      // - a preallocated process.
+      case "web":
+        if (windows.some(w => w.tab)) {
+          return RANK_WEB_TABS;
+        }
+        if (windows.length >= 1) {
+          return RANK_WEB_FRAMES;
+        }
+        // For the time being, we do not display DOM workers
+        // (and there's no API to get information on them).
+        // Once the blockers for bug 1663737 have landed, we'll be able
+        // to find out whether this process has DOM workers. If so, we'll
+        // count this process as a content process.
+        return RANK_PREALLOCATED;
+      // Other special processes before preallocated.
+      default:
+        return RANK_UTILITY;
+    }
+  },
+
+  // Handle events on image controls.
+  _handleActivate(target) {
+    if (target.classList.contains("twisty")) {
+      this._handleTwisty(target);
+      return;
+    }
+    if (target.classList.contains("close-icon")) {
+      this._handleKill(target);
+      return;
+    }
+
+    if (target.classList.contains("profiler-icon")) {
+      this._handleProfiling(target);
+      return;
+    }
+
+    this._handleSelection(target);
+  },
+
+  // Open/close list of threads.
+  _handleTwisty(target) {
+    let row = target.parentNode.parentNode;
+    if (target.classList.toggle("open")) {
+      target.setAttribute("aria-expanded", "true");
+      this._showThreads(row, this._maxSlopeCpu);
+      View.insertAfterRow(row);
+    } else {
+      target.setAttribute("aria-expanded", "false");
+      this._removeSubtree(row);
+    }
+  },
+
+  // Kill process/close tab/close subframe.
+  _handleKill(target) {
+    let row = target.parentNode;
+    if (row.process) {
+      // Kill process immediately.
+      let pid = row.process.pid;
+
+      // Make sure that the user can't click twice on the kill button.
+      // Otherwise, chaos might ensue. Plus we risk crashing under Windows.
+      View._killedRecently.push({ pid });
+
+      // Discard tab contents and show that the process and all its contents are getting killed.
+      row.classList.add("killing");
+      for (
+        let childRow = row.nextSibling;
+        childRow && !childRow.classList.contains("process");
+        childRow = childRow.nextSibling
+      ) {
+        childRow.classList.add("killing");
+        let win = childRow.win;
+        if (win) {
+          View._killedRecently.push({ pid: win.outerWindowId });
+          if (win.tab && win.tab.tabbrowser) {
+            win.tab.tabbrowser.discardBrowser(
+              win.tab.tab,
+              /* aForceDiscard = */ true
+            );
+          }
+        }
+      }
+
+      // Finally, kill the process.
+      const ProcessTools = Cc["@mozilla.org/processtools-service;1"].getService(
+        Ci.nsIProcessToolsService
+      );
+      ProcessTools.kill(pid);
+    } else if (row.win && row.win.tab && row.win.tab.tabbrowser) {
+      // This is a tab, close it.
+      row.win.tab.tabbrowser.removeTab(row.win.tab.tab, {
+        skipPermitUnload: true,
+        animate: true,
+      });
+      View._killedRecently.push({ outerWindowId: row.win.outerWindowId });
+      row.classList.add("killing");
+
+      // If this was the only root window of the process, show that the process is also getting killed.
+      if (row.previousSibling.classList.contains("process")) {
+        let parentRow = row.previousSibling;
+        let roots = 0;
+        for (let win of parentRow.process.windows) {
+          if (win.isProcessRoot) {
+            roots += 1;
+          }
+        }
+        if (roots <= 1) {
+          // Yes, we're the only process root, so the process is dying.
+          //
+          // It might actually become a preloaded process rather than
+          // dying. That's an acceptable error. Even if we display incorrectly
+          // that the process is dying, this error will last only one refresh.
+          View._killedRecently.push({ pid: parentRow.process.pid });
+          parentRow.classList.add("killing");
+        }
+      }
+    }
+  },
+
+  // Handle profiling of a process.
+  _handleProfiling(target) {
+    if (Services.profiler.IsActive()) {
+      return;
+    }
+    Services.profiler.StartProfiler(
+      10000000,
+      1,
+      ["default", "ipcmessages", "power"],
+      ["pid:" + target.parentNode.parentNode.process.pid]
+    );
+    target.classList.add("profiler-active");
+    setTimeout(() => {
+      ProfilerPopupBackground.captureProfile("aboutprofiling");
+      target.classList.remove("profiler-active");
+    }, PROFILE_DURATION * 1000);
+  },
+
+  // Handle selection changes.
+  _handleSelection(target) {
+    let row = target.closest("tr");
+    if (!row) {
+      return;
+    }
+    if (this.selectedRow) {
+      this.selectedRow.removeAttribute("selected");
+      if (this.selectedRow.rowId == row.rowId) {
+        // Clicking the same row again clears the selection.
+        this.selectedRow = null;
+        return;
+      }
+    }
+    row.setAttribute("selected", "true");
+    this.selectedRow = row;
+  },
+};
+
+window.onload = async function () {
+  Control.init();
+
+  // Display immediately the list of processes. CPU values will be missing.
+  await Control.update();
+
+  // After the minimum interval between samples, force an update to show
+  // valid CPU values asap.
+  await new Promise(resolve =>
+    setTimeout(resolve, MINIMUM_INTERVAL_BETWEEN_SAMPLES_MS)
+  );
+  await Control.update(true);
+
+  // Then update at the normal frequency.
+  window.setInterval(() => Control.update(), UPDATE_INTERVAL_MS);
+};