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diff --git a/dom/indexedDB/test/unit/test_connection_idle_maintenance.js b/dom/indexedDB/test/unit/test_connection_idle_maintenance.js
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+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+/* exported testSteps */
+async function testSteps() {
+  // A constant used to deal with small decrease in usage when transactions are
+  // transferred from the WAL file back into the original database, also called
+  // as checkpointing.
+  const cosmologicalConstant = 31768;
+
+  // The length of time that database connections will be held open after all
+  // transactions have completed before doing idle maintenance.
+  const connectionIdleMaintenanceMS = 2 * 1000;
+
+  const name = "test_connection_idle_maintenance";
+  const abc = "abcdefghijklmnopqrstuvwxyz";
+
+  // IndexedDB on Android does `PRAGMA auto_vacuum = FULL`, so the freelist
+  // pages are moved to the end of the database file and the database file is
+  // truncated to remove the freelist pages at every transaction commit.
+  if (mozinfo.os == "android") {
+    info("Test disabled on Android for now");
+    return;
+  }
+
+  info("Creating database");
+
+  let request = indexedDB.open(name, 1);
+
+  let event = await expectingUpgrade(request);
+
+  let database = event.target.result;
+
+  let objectStore = database.createObjectStore(name);
+
+  // Add lots of data...
+  for (let i = 0; i < 10000; i++) {
+    objectStore.add(abc, i);
+  }
+
+  // And then clear it so that maintenance has some space to reclaim.
+  objectStore.clear();
+
+  await expectingSuccess(request);
+
+  info("Getting database usage before maintenance");
+
+  let databaseUsageBeforeMaintenance = await new Promise(function (resolve) {
+    getCurrentUsage(function (request) {
+      resolve(request.result.databaseUsage);
+    });
+  });
+
+  info("Waiting for maintenance to start");
+
+  // This time is a double of connectionIdleMaintenanceMS which should be
+  // pessimistic enough to work with randomly slowed down threads in the chaos
+  // mode.
+  await new Promise(function (resolve) {
+    do_timeout(2 * connectionIdleMaintenanceMS, resolve);
+  });
+
+  info("Waiting for maintenance to finish");
+
+  // This time is a double of connectionIdleMaintenanceMS which should be
+  // pessimistic enough to work with randomly slowed down threads in the chaos
+  // mode.
+  await new Promise(function (resolve) {
+    do_timeout(2 * connectionIdleMaintenanceMS, resolve);
+  });
+
+  info("Getting database usage after maintenance");
+
+  let databaseUsageAfterMaintenance = await new Promise(function (resolve) {
+    getCurrentUsage(function (request) {
+      resolve(request.result.databaseUsage);
+    });
+  });
+
+  info(
+    "Database usage before: " +
+      databaseUsageBeforeMaintenance +
+      ". " +
+      "Database usage after: " +
+      databaseUsageAfterMaintenance
+  );
+
+  // Checkpointing done immediately after the maintenance can slightly decrease
+  // the usage even when the maintenance was not run at all.
+  ok(
+    databaseUsageBeforeMaintenance - databaseUsageAfterMaintenance >=
+      cosmologicalConstant,
+    "Maintenance significantly decreased database usage"
+  );
+}