diff --git a/app/lib/features/settings/presentation/screens/web_engine_settings.dart b/app/lib/features/settings/presentation/screens/web_engine_settings.dart
index ce64009b..ed10f401 100644
--- a/app/lib/features/settings/presentation/screens/web_engine_settings.dart
+++ b/app/lib/features/settings/presentation/screens/web_engine_settings.dart
@@ -463,6 +463,22 @@ class WebEngineSettingsScreen extends HookConsumerWidget {
                   ],
                 ),
               ),
+              SwitchListTile.adaptive(
+                title: const Text('Built-in PDF Viewer'),
+                subtitle: const Text(
+                  'Open PDF files directly in the browser without downloading',
+                ),
+                secondary: const Icon(MdiIcons.filePdfBox),
+                value: engineSettings.enablePdfJs,
+                onChanged: (value) async {
+                  await ref
+                      .read(saveEngineSettingsControllerProvider.notifier)
+                      .save(
+                        (currentSettings) =>
+                            currentSettings.copyWith.enablePdfJs(value),
+                      );
+                },
+              ),
               ListTile(
                 title: const Text('Web Engine Hardening'),
                 contentPadding: const EdgeInsets.symmetric(
diff --git a/app/lib/features/user/data/models/engine_settings.dart b/app/lib/features/user/data/models/engine_settings.dart
index 66d4f295..22f12c73 100644
--- a/app/lib/features/user/data/models/engine_settings.dart
+++ b/app/lib/features/user/data/models/engine_settings.dart
@@ -106,6 +106,8 @@ class EngineSettings extends GeckoEngineSettings with FastEquatable {
     bounceTrackingProtectionMode: bounceTrackingProtectionMode,
   );
 
+  final bool enablePdfJs;
+
   EngineSettings({
     required super.javascriptEnabled,
     required super.trackingProtectionPolicy,
@@ -127,6 +129,7 @@ class EngineSettings extends GeckoEngineSettings with FastEquatable {
     required this.dohDefaultProviderUrl,
     required this.dohExceptionsList,
     required super.fingerprintingProtectionOverrides,
+    required this.enablePdfJs,
   });
 
   EngineSettings.withDefaults({
@@ -150,6 +153,7 @@ class EngineSettings extends GeckoEngineSettings with FastEquatable {
     String? dohDefaultProviderUrl,
     List<String>? dohExceptionsList,
     String? fingerprintingProtectionOverrides,
+    bool? enablePdfJs,
   }) : queryParameterStripping =
            queryParameterStripping ?? QueryParameterStripping.disabled,
        bounceTrackingProtectionMode =
@@ -160,6 +164,7 @@ class EngineSettings extends GeckoEngineSettings with FastEquatable {
        dohDefaultProviderUrl =
            dohDefaultProviderUrl ?? BuiltInDohProviders.quad9.url,
        dohExceptionsList = dohExceptionsList ?? [],
+       enablePdfJs = enablePdfJs ?? true,
        super(
          javascriptEnabled: javascriptEnabled ?? true,
          trackingProtectionPolicy:
@@ -220,5 +225,6 @@ class EngineSettings extends GeckoEngineSettings with FastEquatable {
     dohDefaultProviderUrl,
     dohExceptionsList,
     fingerprintingProtectionOverrides,
+    enablePdfJs,
   ];
 }
diff --git a/app/lib/features/user/data/models/engine_settings.g.dart b/app/lib/features/user/data/models/engine_settings.g.dart
index d4832b33..c7be94e6 100644
--- a/app/lib/features/user/data/models/engine_settings.g.dart
+++ b/app/lib/features/user/data/models/engine_settings.g.dart
@@ -65,6 +65,8 @@ abstract class _$EngineSettingsCWProxy {
     String? fingerprintingProtectionOverrides,
   );
 
+  EngineSettings enablePdfJs(bool enablePdfJs);
+
   /// Creates a new instance with the provided field values.
   /// Passing `null` to a nullable field nullifies it, while `null` for a non-nullable field is ignored. To update a single field use `EngineSettings(...).copyWith.fieldName(value)`.
   ///
@@ -93,6 +95,7 @@ abstract class _$EngineSettingsCWProxy {
     String dohDefaultProviderUrl,
     List<String> dohExceptionsList,
     String? fingerprintingProtectionOverrides,
+    bool enablePdfJs,
   });
 }
 
@@ -200,6 +203,10 @@ class _$EngineSettingsCWProxyImpl implements _$EngineSettingsCWProxy {
     fingerprintingProtectionOverrides: fingerprintingProtectionOverrides,
   );
 
+  @override
+  EngineSettings enablePdfJs(bool enablePdfJs) =>
+      call(enablePdfJs: enablePdfJs);
+
   @override
   /// Creates a new instance with the provided field values.
   /// Passing `null` to a nullable field nullifies it, while `null` for a non-nullable field is ignored. To update a single field use `EngineSettings(...).copyWith.fieldName(value)`.
@@ -231,6 +238,7 @@ class _$EngineSettingsCWProxyImpl implements _$EngineSettingsCWProxy {
     Object? dohDefaultProviderUrl = const $CopyWithPlaceholder(),
     Object? dohExceptionsList = const $CopyWithPlaceholder(),
     Object? fingerprintingProtectionOverrides = const $CopyWithPlaceholder(),
+    Object? enablePdfJs = const $CopyWithPlaceholder(),
   }) {
     return EngineSettings(
       javascriptEnabled: javascriptEnabled == const $CopyWithPlaceholder()
@@ -337,6 +345,11 @@ class _$EngineSettingsCWProxyImpl implements _$EngineSettingsCWProxy {
           ? _value.fingerprintingProtectionOverrides
           // ignore: cast_nullable_to_non_nullable
           : fingerprintingProtectionOverrides as String?,
+      enablePdfJs:
+          enablePdfJs == const $CopyWithPlaceholder() || enablePdfJs == null
+          ? _value.enablePdfJs
+          // ignore: cast_nullable_to_non_nullable
+          : enablePdfJs as bool,
     );
   }
 }
@@ -408,6 +421,7 @@ EngineSettings _$EngineSettingsFromJson(Map<String, dynamic> json) =>
           .toList(),
       fingerprintingProtectionOverrides:
           json['fingerprintingProtectionOverrides'] as String?,
+      enablePdfJs: json['enablePdfJs'] as bool?,
     );
 
 Map<String, dynamic> _$EngineSettingsToJson(
@@ -446,6 +460,7 @@ Map<String, dynamic> _$EngineSettingsToJson(
   'dohProviderUrl': instance.dohProviderUrl,
   'dohDefaultProviderUrl': instance.dohDefaultProviderUrl,
   'dohExceptionsList': instance.dohExceptionsList,
+  'enablePdfJs': instance.enablePdfJs,
 };
 
 const _$TrackingProtectionPolicyEnumMap = {
diff --git a/app/lib/features/user/domain/repositories/engine_settings.dart b/app/lib/features/user/domain/repositories/engine_settings.dart
index 041b7029..11422211 100644
--- a/app/lib/features/user/domain/repositories/engine_settings.dart
+++ b/app/lib/features/user/domain/repositories/engine_settings.dart
@@ -120,6 +120,10 @@ class EngineSettingsRepository extends _$EngineSettingsRepository {
             DriftSqlType.string,
             db.typeMapping,
           ),
+      'enablePdfJs': settings['enablePdfJs']?.readAs(
+        DriftSqlType.bool,
+        db.typeMapping,
+      ),
     });
   }
 
diff --git a/app/lib/features/user/domain/repositories/engine_settings.g.dart b/app/lib/features/user/domain/repositories/engine_settings.g.dart
index 862db30e..ffeb433e 100644
--- a/app/lib/features/user/domain/repositories/engine_settings.g.dart
+++ b/app/lib/features/user/domain/repositories/engine_settings.g.dart
@@ -34,7 +34,7 @@ final class EngineSettingsRepositoryProvider
 }
 
 String _$engineSettingsRepositoryHash() =>
-    r'17a4e505320e92a90ed8b62db263c283c5eaa839';
+    r'cd087c5631faaddf1fced31569b0fd577d6030a7';
 
 abstract class _$EngineSettingsRepository
     extends $StreamNotifier<EngineSettings> {