Fixed collasped categories with no items disappearing

app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryPresenter.kt

@@ -179,9 +179,13 @@ class LibraryPresenter(
 
         val filterTrackers = FilterBottomSheet.FILTER_TRACKER
 
+        val filtersOff = filterDownloaded == 0 && filterUnread == 0 && filterCompleted == 0 && filterTracked == 0 && filterMangaType == 0
         return items.filter f@{ item ->
             if (item.manga.status == -1) {
-                return@f sectionedLibraryItems[item.manga.category]?.any {
+                val subItems = sectionedLibraryItems[item.manga.category]
+                if (subItems.isNullOrEmpty()) return@f filtersOff
+                else {
+                    return@f subItems.any {
                         matchesFilters(
                             it,
                             filterDownloaded,
@@ -191,10 +195,11 @@ class LibraryPresenter(
                             filterMangaType,
                             filterTrackers
                         )
-                } ?: false
+                    }
+                }
             } else if (item.manga.isBlank()) {
                 return@f if (showAllCategories) {
-                    filterDownloaded == 0 && filterUnread == 0 && filterCompleted == 0 && filterTracked == 0 && filterMangaType == 0
+                    filtersOff
                 } else {
                     true
                 }