Misc fixes/improvements from WIP branches

ext/src/background/receiverSelector/ReceiverSelector.ts

@@ -167,9 +167,9 @@ export default class ReceiverSelector extends TypedEventTarget<ReceiverSelectorE
         });
 
         if (
-            !this.receivers ||
-            !this.defaultMediaType ||
-            !this.availableMediaTypes
+            this.receivers === undefined ||
+            this.defaultMediaType === undefined ||
+            this.availableMediaTypes === undefined
         ) {
             throw logger.error("Popup receiver data not found.");
         }

ext/src/background/receiverSelector/index.ts

@@ -1,11 +1,14 @@
 "use strict";
 
+import { ReceiverDevice } from "../../types";
+
 export enum ReceiverSelectorType {
     Popup,
     Native
 }
 
 export enum ReceiverSelectorMediaType {
+    None = 0,
     App = 1,
     Tab = 2,
     Screen = 4,