Merge pull request jupyter-widgets#3475 from kellietay/ipywidgets-issue-3466

fix: Issue 3466 - Disconnect broken link problems

Author: jasongrout

packages/base/css/index.css

@@ -5,7 +5,7 @@
 .jupyter-widgets-disconnected::before {
   content: '\f127'; /* chain-broken */
   display: inline-block;
-  font: normal normal normal 14px/1 FontAwesome;
+  font: normal normal 900 14px/1px 'Font Awesome 5 Free';
   font-size: inherit;
   text-rendering: auto;
   -webkit-font-smoothing: antialiased;