diff --git a/background/background-worker.js b/background/background-worker.js
index 366b7b3c..81387aac 100644
--- a/background/background-worker.js
+++ b/background/background-worker.js
@@ -12,6 +12,7 @@ createAPI({
   compileUsercss,
   parseUsercssMeta(text, indexOffset = 0) {
     loadScript(
+      '/js/polyfill.js',
       '/vendor/usercss-meta/usercss-meta.min.js',
       '/vendor-overwrites/colorpicker/colorconverter.js',
       '/js/meta-parser.js'
@@ -20,6 +21,7 @@ createAPI({
   },
   nullifyInvalidVars(vars) {
     loadScript(
+      '/js/polyfill.js',
       '/vendor/usercss-meta/usercss-meta.min.js',
       '/vendor-overwrites/colorpicker/colorconverter.js',
       '/js/meta-parser.js'
diff --git a/edit.html b/edit.html
index c064d89f..81423113 100644
--- a/edit.html
+++ b/edit.html
@@ -62,6 +62,7 @@
     <script src="vendor-overwrites/colorpicker/colorpicker.js"></script>
     <script src="vendor-overwrites/colorpicker/colorview.js"></script>
 
+    <script src="js/polyfill.js"></script>
     <script src="js/promisify.js"></script>
     <script src="js/dom.js"></script>
     <script src="js/messaging.js"></script>
diff --git a/edit/editor-worker.js b/edit/editor-worker.js
index 62ef380c..6ef51eef 100644
--- a/edit/editor-worker.js
+++ b/edit/editor-worker.js
@@ -16,6 +16,7 @@ createAPI({
   },
   metalint: code => {
     loadScript(
+      '/js/polyfill.js',
       '/vendor/usercss-meta/usercss-meta.min.js',
       '/vendor-overwrites/colorpicker/colorconverter.js',
       '/js/meta-parser.js'
diff --git a/install-usercss.html b/install-usercss.html
index 00e71cb8..84eb5b26 100644
--- a/install-usercss.html
+++ b/install-usercss.html
@@ -9,6 +9,7 @@
   <link href="global.css" rel="stylesheet">
   <link href="install-usercss/install-usercss.css" rel="stylesheet">
 
+  <script src="js/polyfill.js"></script>
   <script src="js/promisify.js"></script>
   <script src="js/msg.js"></script>
   <script src="js/messaging.js"></script>
diff --git a/js/polyfill.js b/js/polyfill.js
new file mode 100644
index 00000000..d2b63a37
--- /dev/null
+++ b/js/polyfill.js
@@ -0,0 +1,6 @@
+if (!Object.entries) {
+  Object.entries = obj => Object.keys(obj).map(k => [k, obj[k]]);
+}
+if (!Object.values) {
+  Object.values = obj => Object.keys(obj).map(k => obj[k]);
+}
diff --git a/manage.html b/manage.html
index dcf3edaa..7754f573 100644
--- a/manage.html
+++ b/manage.html
@@ -146,6 +146,7 @@
     </details>
   </template>
 
+  <script src="js/polyfill.js"></script>
   <script src="js/promisify.js"></script>
   <script src="js/dom.js"></script>
   <script src="js/messaging.js"></script>
diff --git a/manifest.json b/manifest.json
index 11489478..2fe717f0 100644
--- a/manifest.json
+++ b/manifest.json
@@ -24,6 +24,7 @@
   ],
   "background": {
     "scripts": [
+      "js/polyfill.js",
       "js/promisify.js",
       "js/messaging.js",
       "js/msg.js",
@@ -62,7 +63,7 @@
       "run_at": "document_start",
       "all_frames": true,
       "match_about_blank": true,
-      "js": ["js/promisify.js", "js/msg.js", "js/prefs.js", "content/apply.js"]
+      "js": ["js/polyfill.js", "js/promisify.js", "js/msg.js", "js/prefs.js", "content/apply.js"]
     },
     {
       "matches": ["http://userstyles.org/*", "https://userstyles.org/*"],
diff --git a/options.html b/options.html
index 996ca894..d20834b5 100644
--- a/options.html
+++ b/options.html
@@ -19,6 +19,7 @@
     }
   </style>
 
+  <script src="js/polyfill.js"></script>
   <script src="js/dom.js"></script>
   <script src="js/messaging.js"></script>
   <script src="js/promisify.js"></script>
diff --git a/popup.html b/popup.html
index 93eadd4e..35c51cba 100644
--- a/popup.html
+++ b/popup.html
@@ -151,6 +151,7 @@
   <link rel="stylesheet" href="manage/config-dialog.css">
   <script src="manage/config-dialog.js"></script>
 
+  <script src="js/polyfill.js"></script>
   <script src="js/promisify.js"></script>
   <script src="js/dom.js"></script>
   <script src="js/messaging.js"></script>