Fixed: Sorting queue by episode properties when not all items have an episode

frontend/src/Store/Actions/queueActions.js

@@ -77,6 +77,7 @@ export const defaultState = {
       {
         name: 'episode.title',
         label: 'Episode Title',
+        isSortable: true,
         isVisible: true
       },
       {

src/Sonarr.Api.V3/Queue/QueueModule.cs

@@ -151,9 +151,9 @@ namespace Sonarr.Api.V3.Queue
                 case "episode":
                     return q => q.Episode;
                 case "episode.airDateUtc":
-                    return q => q.Episode.AirDateUtc;
+                    return q => q.Episode?.AirDateUtc;
                 case "episode.title":
-                    return q => q.Episode.Title;
+                    return q => q.Episode?.Title;
                 case "language":
                     return q => q.Language;
                 case "quality":