--- a/browser/components/extensions/test/xpcshell/test_ext_browsingData_cookies_cache.js
+++ b/browser/components/extensions/test/xpcshell/test_ext_browsingData_cookies_cache.js
@@ -1,10 +1,11 @@
 /* -*- Mode: indent-tabs-mode: nil; js-indent-level: 2 -*- */
 /* vim: set sts=2 sw=2 et tw=80: */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 "use strict";
 
 XPCOMUtils.defineLazyModuleGetter(this, "setTimeout",
                                   "resource://gre/modules/Timer.jsm");
 
 const COOKIE = {
   host: "example.com",
   name: "test_cookie",

--- a/browser/components/translation/test/unit/test_cld2.js
+++ b/browser/components/translation/test/unit/test_cld2.js
@@ -12,16 +12,17 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
 //
 // Author: dsites@google.com (Dick Sites)
 //
 // Unit test compact language detector, CLD2
 //
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 // Test strings.
 const kTeststr_en =
   "confiscation of goods is assigned as the penalty part most of the courts " +
   "consist of members and when it is necessary to bring public cases before a " +
   "jury of members two courts combine for the purpose the most important cases " +
   "of all are brought jurors or";
 

--- a/browser/experiments/test/xpcshell/test_cacherace.js
+++ b/browser/experiments/test/xpcshell/test_cacherace.js
@@ -1,10 +1,11 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 "use strict";
 
 Cu.import("resource://testing-common/httpd.js");
 Cu.import("resource://gre/modules/Timer.jsm");
 
 const MANIFEST_HANDLER         = "manifests/handler";
 

--- a/browser/extensions/formautofill/test/unit/test_autofillFormFields.js
+++ b/browser/extensions/formautofill/test/unit/test_autofillFormFields.js
@@ -1,11 +1,12 @@
 /*
  * Test for form auto fill content helper fill all inputs function.
  */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 "use strict";
 
 Cu.import("resource://formautofill/FormAutofillHandler.jsm");
 
 const TESTCASES = [
   {
     description: "Form without autocomplete property",

--- a/devtools/server/tests/unit/test_promises_object_timetosettle-02.js
+++ b/devtools/server/tests/unit/test_promises_object_timetosettle-02.js
@@ -1,10 +1,11 @@
 /* Any copyright is dedicated to the Public Domain.
    http://creativecommons.org/publicdomain/zero/1.0/ */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 /**
  * Test that we get the expected settlement time for promise time to settle.
  */
 
 "use strict";
 
 const { PromisesFront } = require("devtools/shared/fronts/promises");

--- a/devtools/shared/discovery/tests/unit/test_discovery.js
+++ b/devtools/shared/discovery/tests/unit/test_discovery.js
@@ -1,10 +1,11 @@
 /* Any copyright is dedicated to the Public Domain.
    http://creativecommons.org/publicdomain/zero/1.0/ */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 "use strict";
 
 var Cu = Components.utils;
 
 const { require } =
   Cu.import("resource://devtools/shared/Loader.jsm", {});
 const Services = require("Services");

--- a/dom/indexedDB/test/unit/test_database_close_without_onclose.js
+++ b/dom/indexedDB/test/unit/test_database_close_without_onclose.js
@@ -1,12 +1,13 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 var testGenerator = testSteps();
 
 function* testSteps()
 {
   const name = this.window ? window.location.pathname :
                              "test_database_close_without_onclose.js";
 

--- a/dom/indexedDB/test/unit/test_idle_maintenance.js
+++ b/dom/indexedDB/test/unit/test_idle_maintenance.js
@@ -1,12 +1,13 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 var testGenerator = testSteps();
 
 function* testSteps()
 {
   let uri = Cc["@mozilla.org/network/io-service;1"].
             getService(Ci.nsIIOService).
             newURI("https://www.example.com");

--- a/dom/indexedDB/test/unit/test_temporary_storage.js
+++ b/dom/indexedDB/test/unit/test_temporary_storage.js
@@ -1,12 +1,13 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 var testGenerator = testSteps();
 
 function* testSteps()
 {
   const name = this.window ?
                window.location.pathname :
                "test_temporary_storage.js";

--- a/dom/indexedDB/test/unit/test_writer_starvation.js
+++ b/dom/indexedDB/test/unit/test_writer_starvation.js
@@ -1,12 +1,13 @@
 /**
  * Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 if (!this.window) {
   this.runTest = function() {
     todo(false, "Test disabled in xpcshell test suite for now");
     finishTest();
   }
 }
 

--- a/toolkit/components/extensions/test/xpcshell/test_ext_alarms.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_alarms.js
@@ -1,10 +1,11 @@
 /* -*- Mode: indent-tabs-mode: nil; js-indent-level: 2 -*- */
 /* vim: set sts=2 sw=2 et tw=80: */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 "use strict";
 
 add_task(async function test_alarm_without_permissions() {
   function backgroundScript() {
     browser.test.assertTrue(!browser.alarms,
                             "alarm API is not available when the alarm permission is not required");
     browser.test.notifyPass("alarms_permission");
   }

--- a/toolkit/components/extensions/test/xpcshell/test_ext_alarms_does_not_fire.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_alarms_does_not_fire.js
@@ -1,10 +1,11 @@
 /* -*- Mode: indent-tabs-mode: nil; js-indent-level: 2 -*- */
 /* vim: set sts=2 sw=2 et tw=80: */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 "use strict";
 
 add_task(async function test_cleared_alarm_does_not_fire() {
   async function backgroundScript() {
     let ALARM_NAME = "test_ext_alarms";
 
     browser.alarms.onAlarm.addListener(alarm => {
       browser.test.fail("cleared alarm does not fire");

--- a/toolkit/components/extensions/test/xpcshell/test_ext_alarms_periodic.js
+++ b/toolkit/components/extensions/test/xpcshell/test_ext_alarms_periodic.js
@@ -1,10 +1,11 @@
 /* -*- Mode: indent-tabs-mode: nil; js-indent-level: 2 -*- */
 /* vim: set sts=2 sw=2 et tw=80: */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 "use strict";
 
 add_task(async function test_periodic_alarm_fires() {
   function backgroundScript() {
     const ALARM_NAME = "test_ext_alarms";
     let count = 0;
     let timer;
 

--- a/toolkit/components/promiseworker/tests/xpcshell/test_Promise.js
+++ b/toolkit/components/promiseworker/tests/xpcshell/test_Promise.js
@@ -1,10 +1,11 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 "use strict";
 
 var Cu = Components.utils;
 
 Cu.import("resource://gre/modules/PromiseWorker.jsm", this);
 Cu.import("resource://gre/modules/Timer.jsm", this);
 

--- a/toolkit/components/search/tests/xpcshell/test_searchSuggest.js
+++ b/toolkit/components/search/tests/xpcshell/test_searchSuggest.js
@@ -1,10 +1,11 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 /**
  * Testing search suggestions from SearchSuggestionController.jsm.
  */
 
 "use strict";
 
 Cu.import("resource://gre/modules/FormHistory.jsm");

--- a/toolkit/components/telemetry/tests/unit/test_PingSender.js
+++ b/toolkit/components/telemetry/tests/unit/test_PingSender.js
@@ -1,11 +1,12 @@
 /* Any copyright is dedicated to the Public Domain.
    http://creativecommons.org/publicdomain/zero/1.0/
 */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 // This tests submitting a ping using the stand-alone pingsender program.
 
 "use strict";
 
 Cu.import("resource://gre/modules/osfile.jsm", this);
 Cu.import("resource://gre/modules/Preferences.jsm", this);
 Cu.import("resource://gre/modules/PromiseUtils.jsm", this);

--- a/toolkit/components/terminator/tests/xpcshell/test_terminator_record.js
+++ b/toolkit/components/terminator/tests/xpcshell/test_terminator_record.js
@@ -1,10 +1,11 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 "use strict";
 
 
 // Test that the Shutdown Terminator records durations correctly
 
 var Cu = Components.utils;
 var Cc = Components.classes;

--- a/toolkit/modules/subprocess/test/xpcshell/test_subprocess.js
+++ b/toolkit/modules/subprocess/test/xpcshell/test_subprocess.js
@@ -1,8 +1,9 @@
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 "use strict";
 
 Cu.import("resource://gre/modules/AppConstants.jsm");
 Cu.import("resource://gre/modules/Timer.jsm");
 
 
 const env = Cc["@mozilla.org/process/environment;1"].getService(Ci.nsIEnvironment);
 

--- a/toolkit/modules/tests/xpcshell/test_GMPInstallManager.js
+++ b/toolkit/modules/tests/xpcshell/test_GMPInstallManager.js
@@ -1,10 +1,11 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 var {classes: Cc, interfaces: Ci, results: Cr, utils: Cu, manager: Cm} = Components;
 const URL_HOST = "http://localhost";
 
 var GMPScope = Cu.import("resource://gre/modules/GMPInstallManager.jsm", {});
 var GMPInstallManager = GMPScope.GMPInstallManager;
 
 Cu.import("resource://gre/modules/Timer.jsm");

--- a/toolkit/modules/tests/xpcshell/test_PromiseUtils.js
+++ b/toolkit/modules/tests/xpcshell/test_PromiseUtils.js
@@ -1,10 +1,11 @@
   /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
 
 "use strict";
 
 Components.utils.import("resource://gre/modules/PromiseUtils.jsm");
 Components.utils.import("resource://gre/modules/Timer.jsm");
 Components.utils.import("resource://testing-common/PromiseTestUtils.jsm");
 
 // Tests for PromiseUtils.jsm

--- a/tools/lint/eslint/eslint-plugin-mozilla/lib/configs/xpcshell-test.js
+++ b/tools/lint/eslint/eslint-plugin-mozilla/lib/configs/xpcshell-test.js
@@ -64,11 +64,12 @@ module.exports = {
     // eslint-disable-next-line max-len
     // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/uneval
     "uneval": false
   },
 
   rules: {
     "mozilla/import-headjs-globals": "warn",
     "mozilla/mark-test-function-used": "warn",
+    "mozilla/no-arbitrary-setTimeout": "error",
     "no-shadow": "error"
   }
 };