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diff --git a/tools/lint/eslint/eslint-plugin-mozilla/lib/configs/recommended.js b/tools/lint/eslint/eslint-plugin-mozilla/lib/configs/recommended.js
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+/* 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";
+
+/**
+ * The configuration is based on eslint:recommended config. The details for all
+ * the ESLint rules, and which ones are in the recommended configuration can
+ * be found here:
+ *
+ * https://eslint.org/docs/rules/
+ *
+ * Rules that we've explicitly decided not to enable:
+ *
+ *   require-await - bug 1381030.
+ *   no-prototype-builtins - bug 1551829.
+ *   require-atomic-updates - bug 1551829.
+ *     - This generates too many false positives that are not easy to work
+ *       around, and false positives seem to be inherent in the rule.
+ */
+module.exports = {
+  env: {
+    browser: true,
+    es2022: true,
+    "mozilla/privileged": true,
+    "mozilla/specific": true,
+  },
+
+  // The prettier configuration here comes from eslint-config-prettier and
+  // turns off all of ESLint's rules related to formatting.
+  extends: [
+    "eslint:recommended",
+    "prettier",
+    "plugin:json/recommended-with-comments",
+  ],
+
+  overrides: [
+    {
+      // System mjs files and jsm files are not loaded in the browser scope,
+      // so we turn that off for those. Though we do have our own special
+      // environment for them.
+      env: {
+        browser: false,
+        "mozilla/jsm": true,
+      },
+      files: ["**/*.sys.mjs", "**/*.jsm"],
+      rules: {
+        "mozilla/lazy-getter-object-name": "error",
+        "mozilla/reject-eager-module-in-lazy-getter": "error",
+        "mozilla/reject-global-this": "error",
+        "mozilla/reject-globalThis-modification": "error",
+        // For all system modules, we expect no properties to need importing,
+        // hence reject everything.
+        "mozilla/reject-importGlobalProperties": ["error", "everything"],
+        "mozilla/reject-mixing-eager-and-lazy": "error",
+        "mozilla/reject-top-level-await": "error",
+        // TODO: Bug 1575506 turn `builtinGlobals` on here.
+        // We can enable builtinGlobals for jsms due to their scopes.
+        "no-redeclare": ["error", { builtinGlobals: false }],
+      },
+    },
+    {
+      files: ["**/*.mjs", "**/*.jsx", "**/*.jsm", "**/?(*.)worker.?(m)js"],
+      rules: {
+        // Modules and workers are far easier to check for no-unused-vars on a
+        // global scope, than our content files. Hence we turn that on here.
+        "no-unused-vars": [
+          "error",
+          {
+            args: "none",
+            vars: "all",
+          },
+        ],
+      },
+    },
+    {
+      excludedFiles: ["**/*.sys.mjs"],
+      files: ["**/*.mjs"],
+      rules: {
+        "mozilla/reject-import-system-module-from-non-system": "error",
+        "mozilla/reject-lazy-imports-into-globals": "error",
+        "no-shadow": ["error", { allow: ["event"], builtinGlobals: true }],
+      },
+    },
+    {
+      files: ["**/*.mjs", "**/*.jsx"],
+      parserOptions: {
+        sourceType: "module",
+      },
+      rules: {
+        "mozilla/use-static-import": "error",
+        // This rule defaults to not allowing "use strict" in module files since
+        // they are always loaded in strict mode.
+        strict: "error",
+      },
+    },
+    {
+      files: ["**/*.jsm"],
+      rules: {
+        "mozilla/mark-exported-symbols-as-used": "error",
+      },
+    },
+    {
+      env: {
+        browser: false,
+        "mozilla/privileged": false,
+        "mozilla/sjs": true,
+        "mozilla/specific": false,
+      },
+      files: ["**/*.sjs"],
+      rules: {
+        // For sjs files, reject everything as we should update the sandbox
+        // to include the globals we need, as these are test-only files.
+        "mozilla/reject-importGlobalProperties": ["error", "everything"],
+      },
+    },
+    {
+      env: {
+        browser: false,
+        worker: true,
+      },
+      files: [
+        // Most files should use the `.worker.` format to be consistent with
+        // other items like `.sys.mjs`, but we allow simply calling the file
+        // "worker" as well.
+        "**/?(*.)worker.?(m)js",
+      ],
+    },
+  ],
+
+  parserOptions: {
+    ecmaVersion: "latest",
+  },
+
+  // When adding items to this file please check for effects on sub-directories.
+  plugins: ["fetch-options", "html", "json", "no-unsanitized"],
+
+  // When adding items to this file please check for effects on all of toolkit
+  // and browser
+  rules: {
+    // This may conflict with prettier, so we turn it off.
+    "arrow-body-style": "off",
+
+    // Warn about cyclomatic complexity in functions.
+    // XXX Get this down to 20?
+    complexity: ["error", 34],
+
+    // Functions must always return something or nothing
+    "consistent-return": "error",
+
+    // XXX This rule line should be removed to enable it. See bug 1487642.
+    // Require super() calls in constructors
+    "constructor-super": "off",
+
+    // Require braces around blocks that start a new line
+    curly: ["error", "all"],
+
+    // Encourage the use of dot notation whenever possible.
+    "dot-notation": "error",
+
+    // XXX This rule should be enabled, see Bug 1557040
+    // No credentials submitted with fetch calls
+    "fetch-options/no-fetch-credentials": "off",
+
+    // XXX This rule line should be removed to enable it. See bug 1487642.
+    // Enforce return statements in getters
+    "getter-return": "off",
+
+    // Don't enforce the maximum depth that blocks can be nested. The complexity
+    // rule is a better rule to check this.
+    "max-depth": "off",
+
+    // Maximum depth callbacks can be nested.
+    "max-nested-callbacks": ["error", 10],
+
+    "mozilla/avoid-removeChild": "error",
+    "mozilla/consistent-if-bracing": "error",
+    "mozilla/import-browser-window-globals": "error",
+    "mozilla/import-globals": "error",
+    "mozilla/no-compare-against-boolean-literals": "error",
+    "mozilla/no-cu-reportError": "error",
+    "mozilla/no-define-cc-etc": "error",
+    "mozilla/no-throw-cr-literal": "error",
+    "mozilla/no-useless-parameters": "error",
+    "mozilla/no-useless-removeEventListener": "error",
+    "mozilla/prefer-boolean-length-check": "error",
+    "mozilla/prefer-formatValues": "error",
+    "mozilla/reject-addtask-only": "error",
+    "mozilla/reject-chromeutils-import-params": "error",
+    "mozilla/reject-importGlobalProperties": ["error", "allownonwebidl"],
+    "mozilla/reject-multiple-getters-calls": "error",
+    "mozilla/reject-scriptableunicodeconverter": "warn",
+    "mozilla/rejects-requires-await": "error",
+    "mozilla/use-cc-etc": "error",
+    "mozilla/use-chromeutils-definelazygetter": "error",
+    "mozilla/use-chromeutils-generateqi": "error",
+    "mozilla/use-chromeutils-import": "error",
+    "mozilla/use-console-createInstance": "error",
+    "mozilla/use-default-preference-values": "error",
+    "mozilla/use-includes-instead-of-indexOf": "error",
+    "mozilla/use-isInstance": "error",
+    "mozilla/use-ownerGlobal": "error",
+    "mozilla/use-returnValue": "error",
+    "mozilla/use-services": "error",
+    "mozilla/valid-lazy": "error",
+    "mozilla/valid-services": "error",
+
+    // Use [] instead of Array()
+    "no-array-constructor": "error",
+
+    // Disallow use of arguments.caller or arguments.callee.
+    "no-caller": "error",
+
+    // XXX Bug 1487642 - decide if we want to enable this or not.
+    // Disallow lexical declarations in case clauses
+    "no-case-declarations": "off",
+
+    // XXX Bug 1487642 - decide if we want to enable this or not.
+    // Disallow the use of console
+    "no-console": "off",
+
+    // Disallows expressions where the operation doesn't affect the value.
+    // TODO: This is enabled by default in ESLint's v9 recommended configuration.
+    "no-constant-binary-expression": "error",
+
+    // XXX Bug 1487642 - decide if we want to enable this or not.
+    // Disallow constant expressions in conditions
+    "no-constant-condition": "off",
+
+    // If an if block ends with a return no need for an else block
+    "no-else-return": "error",
+
+    // No empty statements
+    "no-empty": ["error", { allowEmptyCatch: true }],
+
+    // Disallow eval and setInteral/setTimeout with strings
+    "no-eval": "error",
+
+    // Disallow unnecessary calls to .bind()
+    "no-extra-bind": "error",
+
+    // Disallow fallthrough of case statements
+    "no-fallthrough": [
+      "error",
+      {
+        // The eslint rule doesn't allow for case-insensitive regex option.
+        // The following pattern allows for a dash between "fall through" as
+        // well as alternate spelling of "fall thru". The pattern also allows
+        // for an optional "s" at the end of "fall" ("falls through").
+        commentPattern:
+          "[Ff][Aa][Ll][Ll][Ss]?[\\s-]?([Tt][Hh][Rr][Oo][Uu][Gg][Hh]|[Tt][Hh][Rr][Uu])",
+      },
+    ],
+
+    // Disallow eval and setInteral/setTimeout with strings
+    "no-implied-eval": "error",
+
+    // This has been superseded since we're using ES6.
+    // Disallow variable or function declarations in nested blocks
+    "no-inner-declarations": "off",
+
+    // Disallow the use of the __iterator__ property
+    "no-iterator": "error",
+
+    // No labels
+    "no-labels": "error",
+
+    // Disallow unnecessary nested blocks
+    "no-lone-blocks": "error",
+
+    // No single if block inside an else block
+    "no-lonely-if": "error",
+
+    // Nested ternary statements are confusing
+    "no-nested-ternary": "error",
+
+    // Disallow use of new wrappers
+    "no-new-wrappers": "error",
+
+    // Use {} instead of new Object(), unless arguments are passed.
+    "no-object-constructor": "error",
+
+    // We don't want this, see bug 1551829
+    "no-prototype-builtins": "off",
+
+    // Disable builtinGlobals for no-redeclare as this conflicts with our
+    // globals declarations especially for browser window.
+    "no-redeclare": ["error", { builtinGlobals: false }],
+
+    // Disallow use of event global.
+    "no-restricted-globals": ["error", "event"],
+
+    // No unnecessary comparisons
+    "no-self-compare": "error",
+
+    // No comma sequenced statements
+    "no-sequences": "error",
+
+    // No declaring variables from an outer scope
+    // "no-shadow": "error",
+
+    // Disallow throwing literals (eg. throw "error" instead of
+    // throw new Error("error")).
+    "no-throw-literal": "error",
+
+    // Disallow the use of Boolean literals in conditional expressions.
+    "no-unneeded-ternary": "error",
+
+    // No unsanitized use of innerHTML=, document.write() etc.
+    // cf. https://github.com/mozilla/eslint-plugin-no-unsanitized#rule-details
+    "no-unsanitized/method": "error",
+    "no-unsanitized/property": "error",
+
+    // No declaring variables that are never used
+    "no-unused-vars": [
+      "error",
+      {
+        args: "none",
+        vars: "local",
+      },
+    ],
+
+    // No using variables before defined
+    // "no-use-before-define": ["error", "nofunc"],
+
+    // Disallow unnecessary .call() and .apply()
+    "no-useless-call": "error",
+
+    // Don't concatenate string literals together (unless they span multiple
+    // lines)
+    "no-useless-concat": "error",
+
+    // XXX Bug 1487642 - decide if we want to enable this or not.
+    // Disallow unnecessary escape characters
+    "no-useless-escape": "off",
+
+    // Disallow redundant return statements
+    "no-useless-return": "error",
+
+    // Require object-literal shorthand with ES6 method syntax
+    "object-shorthand": ["error", "always", { avoidQuotes: true }],
+
+    // This may conflict with prettier, so turn it off.
+    "prefer-arrow-callback": "off",
+
+    // XXX Bug 1487642 - decide if we want to enable this or not.
+    // Require generator functions to contain yield
+    "require-yield": "off",
+  },
+};