new file mode 100644
--- /dev/null
+++ b/toolkit/components/addoncompat/ShimWaiver.jsm
@@ -0,0 +1,15 @@
+// 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/.
+
+this.EXPORTED_SYMBOLS = ["ShimWaiver"];
+
+this.ShimWaiver = {
+  getProperty: function(obj, prop) {
+    let rv = obj[prop];
+    if (rv instanceof Function) {
+      rv = rv.bind(obj);
+    }
+    return rv;
+  }
+};

--- a/toolkit/components/addoncompat/moz.build
+++ b/toolkit/components/addoncompat/moz.build
@@ -12,9 +12,10 @@ EXTRA_COMPONENTS += [
     'multiprocessShims.js',
 ]
 
 EXTRA_JS_MODULES += [
     'CompatWarning.jsm',
     'Prefetcher.jsm',
     'RemoteAddonsChild.jsm',
     'RemoteAddonsParent.jsm',
+    'ShimWaiver.jsm'
 ]