--- a/js/xpconnect/loader/mozJSComponentLoader.cpp
+++ b/js/xpconnect/loader/mozJSComponentLoader.cpp
@@ -561,18 +561,16 @@ mozJSComponentLoader::ReuseGlobal(bool a
 
     return true;
 }
 
 JSObject*
 mozJSComponentLoader::GetSharedGlobal(JSContext* aCx)
 {
     if (!mLoaderGlobal) {
-        MOZ_ASSERT(mShareLoaderGlobal);
-
         JS::RootedObject globalObj(aCx);
         CreateLoaderGlobal(aCx, NS_LITERAL_CSTRING("shared JSM global"),
                            nullptr, &globalObj);
 
         // If we fail to create a module global this early, we're not going to
         // get very far, so just bail out now.
         MOZ_RELEASE_ASSERT(globalObj);
         mLoaderGlobal = globalObj;

--- a/js/xpconnect/loader/mozJSComponentLoader.h
+++ b/js/xpconnect/loader/mozJSComponentLoader.h
@@ -72,22 +72,17 @@ class mozJSComponentLoader final : publi
     virtual ~mozJSComponentLoader();
 
     friend class mozilla::ScriptPreloader;
 
     JSObject* CompilationScope(JSContext* aCx)
     {
         if (mLoaderGlobal)
             return mLoaderGlobal;
-        if ((mInitialized || NS_SUCCEEDED(ReallyInit())) &&
-            mShareLoaderGlobal)
-        {
-            return GetSharedGlobal(aCx);
-        }
-        return xpc::CompilationScope();
+        return GetSharedGlobal(aCx);
     }
 
  private:
     static mozJSComponentLoader* sSelf;
 
     nsresult ReallyInit();
     void UnloadModules();
 

--- a/js/xpconnect/tests/marionette/test_loader_global_sharing.py
+++ b/js/xpconnect/tests/marionette/test_loader_global_sharing.py
@@ -66,18 +66,16 @@ class TestLoaderGlobalSharing(Marionette
           Cu.import("resource://gre/modules/Services.jsm");
           window.env = Cc["@mozilla.org/process/environment;1"]
                     .getService(Ci.nsIEnvironment);
         ''')
 
     def setUp(self):
         super(TestLoaderGlobalSharing, self).setUp()
 
-        self.default_pref_value = self.marionette.get_pref(GLOBAL_SHARING_PREF)
-
         self.setUpSession()
 
     def tearDown(self):
         self.marionette.restart(clean=True)
 
         super(TestLoaderGlobalSharing, self).tearDown()
 
     def test_global_sharing_settings(self):
@@ -104,16 +102,12 @@ class TestLoaderGlobalSharing(Marionette
             # defined.
             expect_sharing = pref if var is None else var != '0'
 
             self.restart(prefs={GLOBAL_SHARING_PREF: pref},
                          env={GLOBAL_SHARING_VAR: var})
 
             have_sharing = self.get_global_sharing_enabled()
 
-            # FIXME: User preference values currently do not always take
-            # effect early enough to influence loader behavior.
-            msg = ('Global sharing state should match settings: %r != %r'
-                   % (have_sharing, expect_sharing))
-            if var is not None or pref == self.default_pref_value:
-                self.assertEqual(have_sharing, expect_sharing, msg)
-            elif have_sharing != expect_sharing:
-                print('TEST-EXPECTED-FAIL: ' + msg)
+            self.assertEqual(
+                have_sharing, expect_sharing,
+                'Global sharing state should match settings: %r != %r'
+                % (have_sharing, expect_sharing))