diff --git a/src-ui/src/app/components/document-detail/document-detail.component.ts b/src-ui/src/app/components/document-detail/document-detail.component.ts
index c430526e3..57cb36393 100644
--- a/src-ui/src/app/components/document-detail/document-detail.component.ts
+++ b/src-ui/src/app/components/document-detail/document-detail.component.ts
@@ -212,7 +212,7 @@ export class DocumentDetailComponent
   private componentRouterService = inject(ComponentRouterService)
   private deviceDetectorService = inject(DeviceDetectorService)
   private savedViewService = inject(SavedViewService)
-  private websocketStatusService = inject(WebsocketStatusService)
+  private readonly websocketStatusService = inject(WebsocketStatusService)
 
   @ViewChild('inputTitle')
   titleInput: TextComponent
@@ -460,7 +460,7 @@ export class DocumentDetailComponent
     let formattedModified = null
     if (modified) {
       const parsed = new Date(modified)
-      if (!isNaN(parsed.getTime())) {
+      if (!Number.isNaN(parsed.getTime())) {
         formattedModified = parsed.toLocaleString()
       }
     }
diff --git a/src-ui/src/app/services/websocket-status.service.ts b/src-ui/src/app/services/websocket-status.service.ts
index e2181be97..1711a480a 100644
--- a/src-ui/src/app/services/websocket-status.service.ts
+++ b/src-ui/src/app/services/websocket-status.service.ts
@@ -95,19 +95,20 @@ export class FileStatus {
   providedIn: 'root',
 })
 export class WebsocketStatusService {
-  private settingsService = inject(SettingsService)
+  private readonly settingsService = inject(SettingsService)
 
   private statusWebSocket: WebSocket
 
   private consumerStatus: FileStatus[] = []
 
-  private documentDetectedSubject = new Subject<FileStatus>()
-  private documentConsumptionFinishedSubject = new Subject<FileStatus>()
-  private documentConsumptionFailedSubject = new Subject<FileStatus>()
-  private documentDeletedSubject = new Subject<boolean>()
-  private documentUpdatedSubject =
+  private readonly documentDetectedSubject = new Subject<FileStatus>()
+  private readonly documentConsumptionFinishedSubject =
+    new Subject<FileStatus>()
+  private readonly documentConsumptionFailedSubject = new Subject<FileStatus>()
+  private readonly documentDeletedSubject = new Subject<boolean>()
+  private readonly documentUpdatedSubject =
     new Subject<WebsocketDocumentUpdatedMessage>()
-  private connectionStatusSubject = new Subject<boolean>()
+  private readonly connectionStatusSubject = new Subject<boolean>()
 
   private get(taskId: string, filename?: string) {
     let status =