Added global config for list thumbnails

src/environments/environment.test.ts

@@ -200,6 +200,7 @@ export const environment: BuildConfig = {
     // The absolute lowest year to display in the dropdown (only used when no lowest date can be found for all items)
     defaultLowerLimit: 1900,
   },
+  showItemThumbnails: false,
   item: {
     edit: {
       undoTimeout: 10000 // 10 seconds