diff --git a/app/assets/javascripts/miq_api.js b/app/assets/javascripts/miq_api.js
index ff4fae778cb..8bd7619d235 100644
--- a/app/assets/javascripts/miq_api.js
+++ b/app/assets/javascripts/miq_api.js
@@ -49,8 +49,6 @@
   API.post = withData('POST');
   API.put = withData('PUT');
 
-  var base64encode = window.btoa; // browser api
-
   API.login = function(login, password) {
     API.logout();
 
diff --git a/app/javascript/packs/compat-common.js b/app/javascript/packs/compat-common.js
new file mode 100644
index 00000000000..4567fdaadcf
--- /dev/null
+++ b/app/javascript/packs/compat-common.js
@@ -0,0 +1,8 @@
+import base64js from 'base64-js';
+import TextEncoderLite from 'text-encoder-lite';
+
+// utf8-capable window.btoa
+window.base64encode = (str, encoding = 'utf-8') => {
+  let bytes = new (TextEncoder || TextEncoderLite)(encoding).encode(str);
+  return base64js.fromByteArray(bytes);
+};
diff --git a/app/views/layouts/login.html.haml b/app/views/layouts/login.html.haml
index 1da31406e7b..ecc23782aff 100644
--- a/app/views/layouts/login.html.haml
+++ b/app/views/layouts/login.html.haml
@@ -11,6 +11,12 @@
       = javascript_include_tag 'miq_debug'
       = stylesheet_link_tag 'miq_debug'
 
+    = javascript_pack_tag 'vendor'
+    -# FIXME: the conditional below is a temporary fix for a webpacker issue, remove when it's resolved
+    - unless Rails.env.test?
+      - Webpacker::Manifest.instance.data.keys.each do |pack|
+        = javascript_pack_tag pack if pack.ends_with? '-common.js'
+
     = render :partial => 'layouts/i18n_js'
 
   %body{:class => ::Settings.server.custom_login_logo ? 'whitelabel' : ''}
diff --git a/package.json b/package.json
index 25499b97e42..eeb33690eb9 100644
--- a/package.json
+++ b/package.json
@@ -22,8 +22,10 @@
     "@angular/core": "~4.0.3",
     "@angular/platform-browser": "~4.0.3",
     "@angular/platform-browser-dynamic": "~4.0.3",
+    "base64-js": "~1.2.3",
     "core-js": "~2.4.1",
     "rxjs": "~5.3.0",
+    "text-encoder-lite": "~1.0.1",
     "ui-select": "0.19.8",
     "zone.js": "~0.8.5"
   },