diff --git a/browser/devtools/shared/test/browser.ini b/browser/devtools/shared/test/browser.ini
index 8351047a6a49..b61f8edb784c 100644
--- a/browser/devtools/shared/test/browser.ini
+++ b/browser/devtools/shared/test/browser.ini
@@ -95,7 +95,6 @@ skip-if = e10s # Test intermittently fails with e10s. Bug 1124162.
 [browser_poller.js]
 [browser_prefs-01.js]
 [browser_prefs-02.js]
-[browser_require_basic.js]
 [browser_spectrum.js]
 [browser_theme.js]
 [browser_tableWidget_basic.js]
diff --git a/browser/devtools/shared/test/browser_require_basic.js b/browser/devtools/shared/test/browser_require_basic.js
deleted file mode 100644
index f86974df45b8..000000000000
--- a/browser/devtools/shared/test/browser_require_basic.js
+++ /dev/null
@@ -1,140 +0,0 @@
-/* Any copyright is dedicated to the Public Domain.
- * http://creativecommons.org/publicdomain/zero/1.0/ */
-
-// Tests that source URLs in the Web Console can be clicked to display the
-// standard View Source window.
-
-let [ define, require ] = (function() {
-  let tempScope = {};
-  Components.utils.import("resource://gre/modules/devtools/Require.jsm", tempScope);
-  return [ tempScope.define, tempScope.require ];
-})();
-
-function test() {
-  addTab("about:blank", function() {
-    info("Starting Require Tests");
-    setup();
-
-    testWorking();
-    testDomains();
-    testLeakage();
-    testMultiImport();
-    testRecursive();
-    testUncompilable();
-    testFirebug();
-
-    shutdown();
-  });
-}
-
-function setup() {
-  define('gclitest/requirable', [ 'require', 'exports', 'module' ], function(require, exports, module) {
-    exports.thing1 = 'thing1';
-    exports.thing2 = 2;
-
-    let status = 'initial';
-    exports.setStatus = function(aStatus) { status = aStatus; };
-    exports.getStatus = function() { return status; };
-  });
-
-  define('gclitest/unrequirable', [ 'require', 'exports', 'module' ], function(require, exports, module) {
-    null.throwNPE();
-  });
-
-  define('gclitest/recurse', [ 'require', 'exports', 'module', 'gclitest/recurse' ], function(require, exports, module) {
-    require('gclitest/recurse');
-  });
-
-  define('gclitest/firebug', [ 'gclitest/requirable' ], function(requirable) {
-    return { requirable: requirable, fb: true };
-  });
-}
-
-function shutdown() {
-  delete define.modules['gclitest/requirable'];
-  delete define.globalDomain.modules['gclitest/requirable'];
-  delete define.modules['gclitest/unrequirable'];
-  delete define.globalDomain.modules['gclitest/unrequirable'];
-  delete define.modules['gclitest/recurse'];
-  delete define.globalDomain.modules['gclitest/recurse'];
-  delete define.modules['gclitest/firebug'];
-  delete define.globalDomain.modules['gclitest/firebug'];
-
-  define = undefined;
-  require = undefined;
-
-  finish();
-}
-
-function testWorking() {
-  // There are lots of requirement tests that we could be doing here
-  // The fact that we can get anything at all working is a testament to
-  // require doing what it should - we don't need to test the
-  let requireable = require('gclitest/requirable');
-  is('thing1', requireable.thing1, 'thing1 was required');
-  is(2, requireable.thing2, 'thing2 was required');
-  is(requireable.thing3, undefined, 'thing3 was not required');
-}
-
-function testDomains() {
-  let requireable = require('gclitest/requirable');
-  is(requireable.status, undefined, 'requirable has no status');
-  requireable.setStatus(null);
-  is(null, requireable.getStatus(), 'requirable.getStatus changed to null');
-  is(requireable.status, undefined, 'requirable still has no status');
-  requireable.setStatus('42');
-  is('42', requireable.getStatus(), 'requirable.getStatus changed to 42');
-  is(requireable.status, undefined, 'requirable *still* has no status');
-
-  let domain = new define.Domain();
-  let requireable2 = domain.require('gclitest/requirable');
-  is(requireable2.status, undefined, 'requirable2 has no status');
-  is('initial', requireable2.getStatus(), 'requirable2.getStatus is initial');
-  requireable2.setStatus(999);
-  is(999, requireable2.getStatus(), 'requirable2.getStatus changed to 999');
-  is(requireable2.status, undefined, 'requirable2 still has no status');
-
-  is('42', requireable.getStatus(), 'status 42');
-  ok(requireable.status === undefined, 'requirable has no status (as expected)');
-
-  delete domain.modules['gclitest/requirable'];
-}
-
-function testLeakage() {
-  let requireable = require('gclitest/requirable');
-  is(requireable.setup, null, 'leakage of setup');
-  is(requireable.shutdown, null, 'leakage of shutdown');
-  is(requireable.testWorking, null, 'leakage of testWorking');
-}
-
-function testMultiImport() {
-  let r1 = require('gclitest/requirable');
-  let r2 = require('gclitest/requirable');
-  is(r1, r2, 'double require was strict equal');
-}
-
-function testUncompilable() {
-  // It's not totally clear how a module loader should perform with unusable
-  // modules, however at least it should go into a flat spin ...
-  // GCLI mini_require reports an error as it should
-  try {
-    let unrequireable = require('gclitest/unrequirable');
-    fail();
-  }
-  catch (ex) {
-    // an exception is expected
-  }
-}
-
-function testRecursive() {
-  // See Bug 658583
-  // require('gclitest/recurse');
-  // Also see the comments in the testRecursive() function
-}
-
-function testFirebug() {
-  let requirable = require('gclitest/requirable');
-  let firebug = require('gclitest/firebug');
-  ok(firebug.fb, 'firebug.fb is true');
-  is(requirable, firebug.requirable, 'requirable pass-through');
-}
diff --git a/toolkit/devtools/Require.jsm b/toolkit/devtools/Require.jsm
deleted file mode 100644
index ab72b526b72b..000000000000
--- a/toolkit/devtools/Require.jsm
+++ /dev/null
@@ -1,195 +0,0 @@
-/* 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";
-
-/**
- * Require.jsm is a small module loader that loads JavaScript modules as
- * defined by AMD/RequireJS and CommonJS, or specifically as used by:
- * GCLI, Orion, Firebug, CCDump, NetPanel/HTTPMonitor and others.
- *
- * To date, no attempt has been made to ensure that Require.jsm closely follows
- * either the AMD or CommonJS specs. It is hoped that a more formal JavaScript
- * module standard will arrive before this is necessary. In the mean time it
- * serves the projects it loads.
- */
-
-this.EXPORTED_SYMBOLS = [ "define", "require" ];
-
-const console = (function() {
-  const tempScope = {};
-  Components.utils.import("resource://gre/modules/devtools/Console.jsm", tempScope);
-  return tempScope.console;
-})();
-
-/**
- * Define a module along with a payload.
- * @param moduleName Name for the payload
- * @param deps Ignored. For compatibility with CommonJS AMD Spec
- * @param payload Function with (require, exports, module) params
- */
-this.define = function define(moduleName, deps, payload) {
-  if (typeof moduleName != "string") {
-    throw new Error("Error: Module name is not a string");
-  }
-
-  if (arguments.length == 2) {
-    payload = deps;
-  }
-  else {
-    payload.deps = deps;
-  }
-
-  if (define.debugDependencies) {
-    console.log("define: " + moduleName + " -> " + payload.toString()
-        .slice(0, 40).replace(/\n/, '\\n').replace(/\r/, '\\r') + "...");
-  }
-
-  if (moduleName in define.modules) {
-    throw new Error("Error: Redefining module: " + moduleName);
-  }
-
-  // Mark the payload so we know we need to call it to get the real module
-  payload.__uncompiled = true;
-  define.modules[moduleName] = payload;
-}
-
-/**
- * The global store of un-instantiated modules
- */
-define.modules = {};
-
-/**
- * Should we console.log on module definition/instantiation/requirement?
- */
-define.debugDependencies = false;
-
-
-/**
- * We invoke require() in the context of a Domain so we can have multiple
- * sets of modules running separate from each other.
- * This contrasts with JSMs which are singletons, Domains allows us to
- * optionally load a CommonJS module twice with separate data each time.
- * Perhaps you want 2 command lines with a different set of commands in each,
- * for example.
- */
-function Domain() {
-  this.modules = {};
-
-  if (define.debugDependencies) {
-    this.depth = "";
-  }
-}
-
-/**
- * Lookup module names and resolve them by calling the definition function if
- * needed.
- * There are 2 ways to call this, either with an array of dependencies and a
- * callback to call when the dependencies are found (which can happen
- * asynchronously in an in-page context) or with a single string an no
- * callback where the dependency is resolved synchronously and returned.
- * The API is designed to be compatible with the CommonJS AMD spec and
- * RequireJS.
- * @param deps A name, or array of names for the payload
- * @param callback Function to call when the dependencies are resolved
- * @return The module required or undefined for array/callback method
- */
-Domain.prototype.require = function(config, deps, callback) {
-  if (arguments.length <= 2) {
-    callback = deps;
-    deps = config;
-    config = undefined;
-  }
-
-  if (Array.isArray(deps)) {
-    var params = deps.map(function(dep) {
-      return this.lookup(dep);
-    }, this);
-    if (callback) {
-      callback.apply(null, params);
-    }
-    return undefined;
-  }
-  else {
-    return this.lookup(deps);
-  }
-};
-
-/**
- * Lookup module names and resolve them by calling the definition function if
- * needed.
- * @param moduleName A name for the payload to lookup
- * @return The module specified by aModuleName or null if not found
- */
-Domain.prototype.lookup = function(moduleName) {
-  if (moduleName in this.modules) {
-    var module = this.modules[moduleName];
-    if (define.debugDependencies) {
-      console.log(this.depth + " Using module: " + moduleName);
-    }
-    return module;
-  }
-
-  if (!(moduleName in define.modules)) {
-    throw new Error("Missing module: " + moduleName);
-  }
-
-  var module = define.modules[moduleName];
-
-  if (define.debugDependencies) {
-    console.log(this.depth + " Compiling module: " + moduleName);
-  }
-
-  if (module.__uncompiled) {
-    if (define.debugDependencies) {
-      this.depth += ".";
-    }
-
-    var exports = {};
-    try {
-      var params = module.deps.map((dep) => {
-        if (dep === "require") {
-          return this.require.bind(this);
-        }
-        if (dep === "exports") {
-          return exports;
-        }
-        if (dep === "module") {
-          return { id: moduleName, uri: "" };
-        }
-        return this.lookup(dep);
-      });
-
-      var reply = module.apply(null, params);
-      module = (reply !== undefined) ? reply : exports;
-    }
-    catch (ex) {
-      dump("Error using module '" + moduleName + "' - " + ex + "\n");
-      throw ex;
-    }
-
-    if (define.debugDependencies) {
-      this.depth = this.depth.slice(0, -1);
-    }
-  }
-
-  // cache the resulting module object for next time
-  this.modules[moduleName] = module;
-
-  return module;
-};
-
-/**
- * Expose the Domain constructor and a global domain (on the define function
- * to avoid exporting more than we need. This is a common pattern with
- * require systems)
- */
-define.Domain = Domain;
-define.globalDomain = new Domain();
-
-/**
- * Expose a default require function which is the require of the global
- * sandbox to make it easy to use.
- */
-this.require = define.globalDomain.require.bind(define.globalDomain);
diff --git a/toolkit/devtools/moz.build b/toolkit/devtools/moz.build
index 11db268096ec..3a2a9c4e5b81 100644
--- a/toolkit/devtools/moz.build
+++ b/toolkit/devtools/moz.build
@@ -44,7 +44,6 @@ EXTRA_JS_MODULES.devtools += [
 EXTRA_JS_MODULES.devtools += [
     'Console.jsm',
     'Loader.jsm',
-    'Require.jsm',
 ]
 
 EXTRA_JS_MODULES.devtools.server.actors += [