diff --git a/assets/default_themes/dark.zip b/assets/default_themes/dark.zip
index e2291ba2b..9823262a9 100644
Binary files a/assets/default_themes/dark.zip and b/assets/default_themes/dark.zip differ
diff --git a/assets/default_themes/light.zip b/assets/default_themes/light.zip
index c9579152d..649716126 100644
Binary files a/assets/default_themes/light.zip and b/assets/default_themes/light.zip differ
diff --git a/lib/main.dart b/lib/main.dart
index d2ef627f8..2af01e602 100644
--- a/lib/main.dart
+++ b/lib/main.dart
@@ -189,6 +189,27 @@ void main() async {
   // check and update or install default themes
   await ThemeService.instance.checkDefaultThemesOnStartup();
 
+  // verify current user preference theme and revert to default
+  // if problems are found to prevent app being unusable
+  if (!(await ThemeService.instance
+      .verifyInstalled(themeId: Prefs.instance.themeId))) {
+    Prefs.instance.themeId = "light";
+  }
+
+  // verify current user preference light brightness theme and revert to default
+  // if problems are found to prevent app being unusable
+  if (!(await ThemeService.instance
+      .verifyInstalled(themeId: Prefs.instance.systemBrightnessLightThemeId))) {
+    Prefs.instance.systemBrightnessLightThemeId = "light";
+  }
+
+  // verify current user preference dark brightness theme and revert to default
+  // if problems are found to prevent app being unusable
+  if (!(await ThemeService.instance
+      .verifyInstalled(themeId: Prefs.instance.systemBrightnessDarkThemeId))) {
+    Prefs.instance.systemBrightnessDarkThemeId = "dark";
+  }
+
   runApp(const ProviderScope(child: MyApp()));
 }
 
diff --git a/lib/models/isar/stack_theme.dart b/lib/models/isar/stack_theme.dart
index f072feb02..a76be7ad9 100644
--- a/lib/models/isar/stack_theme.dart
+++ b/lib/models/isar/stack_theme.dart
@@ -1507,7 +1507,7 @@ class StackTheme {
               themeId: json["id"] as String,
             )
           : null
-      ..assetsV2 = version == 2
+      ..assetsV2 = version >= 2
           ? ThemeAssetsV2.fromJson(
               json: Map<String, dynamic>.from(json["assets"] as Map),
               applicationThemesDirectoryPath: applicationThemesDirectoryPath,
diff --git a/lib/themes/theme_service.dart b/lib/themes/theme_service.dart
index ee831af83..db5b851e1 100644
--- a/lib/themes/theme_service.dart
+++ b/lib/themes/theme_service.dart
@@ -17,7 +17,7 @@ final pThemeService = Provider<ThemeService>((ref) {
 });
 
 class ThemeService {
-  static const _currentDefaultThemeVersion = 2;
+  static const _currentDefaultThemeVersion = 3;
   ThemeService._();
   static ThemeService? _instance;
   static ThemeService get instance => _instance ??= ThemeService._();
@@ -40,9 +40,7 @@ class ThemeService {
       throw Exception("Invalid theme archive: Missing theme.json");
     }
 
-    final OutputStream os = OutputStream();
-    themeJsonFiles.first.decompress(os);
-    final String jsonString = utf8.decode(os.getBytes());
+    final jsonString = utf8.decode(themeJsonFiles.first.content as List<int>);
     final json = jsonDecode(jsonString) as Map;
 
     final theme = StackTheme.fromJson(
@@ -50,6 +48,12 @@ class ThemeService {
       applicationThemesDirectoryPath: themesDir.path,
     );
 
+    try {
+      theme.assets;
+    } catch (_) {
+      throw Exception("Invalid theme: Failed to create assets object");
+    }
+
     final String assetsPath = "${themesDir.path}/${theme.themeId}";
 
     for (final file in archive.files) {
@@ -84,7 +88,10 @@ class ThemeService {
       await db.isar.writeTxn(() async {
         await db.isar.stackThemes.delete(isarId);
       });
-      await Directory("${themesDir.path}/$themeId").delete(recursive: true);
+      final dir = Directory("${themesDir.path}/$themeId");
+      if (dir.existsSync()) {
+        await dir.delete(recursive: true);
+      }
     } else {
       Logging.instance.log(
         "Failed to delete theme $themeId",
@@ -159,9 +166,15 @@ class ThemeService {
 
   // TODO more thorough check/verification of theme
   Future<bool> verifyInstalled({required String themeId}) async {
-    final dbHasTheme =
-        await db.isar.stackThemes.where().themeIdEqualTo(themeId).count() > 0;
-    if (dbHasTheme) {
+    final theme =
+        await db.isar.stackThemes.where().themeIdEqualTo(themeId).findFirst();
+    if (theme != null) {
+      try {
+        theme.assets;
+      } catch (_) {
+        return false;
+      }
+
       final themesDir = await StackFileSystem.applicationThemesDirectory();
       final jsonFileExists =
           await File("${themesDir.path}/$themeId/theme.json").exists();