Perform favicon updates twice in Chrome

See diff for why this arcane magic is needed.

Fixes https://github.com/vector-im/riot-web/issues/11347

src/vector/platform/VectorBasePlatform.js

@@ -85,10 +85,31 @@ export default class VectorBasePlatform extends BasePlatform {
                 bgColor = "#f00";
             }
 
+            const doUpdate = () => {
                 this.favicon.badge(notif, {
                     bgColor: bgColor,
                 });
-        } catch (e) {
+            };
+
+            doUpdate();
+
+            // HACK: Workaround for Chrome 78+ and dependency incompatibility.
+            // The library we use doesn't appear to work in Chrome 78, likely due to their
+            // changes surrounding tab behaviour. Tabs went through a bit of a redesign and
+            // restructuring in Chrome 78, so it's not terribly surprising that the library
+            // doesn't work correctly. The library we use hasn't been updated in years and
+            // does not look easy to fix/fork ourselves - we might as well write our own that
+            // doesn't include animation/webcam/etc support. However, that's a bit difficult
+            // so for now we'll just trigger the update twice.
+            //
+            // Note that trying to reproduce the problem in isolation doesn't seem to work:
+            // see https://gist.github.com/turt2live/5ab87919918adbfd7cfb8f1ad10f2409 for
+            // an example (you'll need your own web server to host that).
+            if (!!window.chrome) {
+                doUpdate();
+            }
+        }
+         catch (e) {
             console.warn(`Failed to set badge count: ${e.message}`);
         }
     }