Display WS state in favicon

matrixgw_frontend/src/widgets/messages/AppIconModifier.tsx

@@ -1,4 +1,5 @@
 import Favicon from "react-favicon";
+import { WSState } from "./MatrixWS";
 
 // Taken from https://github.com/element-hq/element-web/blob/0577e245dac944bd85eea07b93a9762a93062f62/src/favicon.ts
 function getInitialFavicon(): HTMLLinkElement[] {
@@ -21,6 +22,14 @@ let iconPath = getInitialFavicon()[0].getAttribute("href")!;
 
 export function AppIconModifier(p: {
   numberUnread: number;
+  state: string;
 }): React.ReactElement {
-  return <Favicon url={iconPath} alertCount={p.numberUnread} />;
+  const isError = p.state === WSState.Error || p.state === WSState.Closed;
+  return (
+    <Favicon
+      url={iconPath}
+      alertFillColor={isError ? "orange" : undefined}
+      alertCount={isError ? "x" : p.numberUnread}
+    />
+  );
 }