Group viewer options in settings page

lib/l10n/app_en.arb

@@ -313,6 +313,10 @@
 	"@settingsExifSupportTrueSubtitle": {
 		"description": "Subtitle of the EXIF support setting when the value is true. The goal is to warn user about the possible side effects of enabling this setting"
 	},
+	"settingsViewerSectionTitle": "Photo viewer",
+	"@settingsViewerSectionTitle": {
+		"description": "Settings for the photo viewer"
+	},
 	"settingsScreenBrightnessTitle": "Screen brightness",
 	"settingsScreenBrightnessDescription": "Adjust screen brightness when viewing a photo",
 	"@settingsScreenBrightnessDescription": {

lib/l10n/untranslated-messages.txt

@@ -1,5 +1,6 @@
 {
   "el": [
+    "settingsViewerSectionTitle",
     "settingsScreenBrightnessTitle",
     "settingsScreenBrightnessDescription",
     "listEmptyText",
@@ -27,6 +28,7 @@
   ],
 
   "es": [
+    "settingsViewerSectionTitle",
     "settingsScreenBrightnessTitle",
     "settingsScreenBrightnessDescription",
     "helpTooltip",
@@ -34,6 +36,7 @@
   ],
 
   "fr": [
+    "settingsViewerSectionTitle",
     "settingsScreenBrightnessTitle",
     "settingsScreenBrightnessDescription",
     "helpTooltip",
@@ -41,6 +44,7 @@
   ],
 
   "ru": [
+    "settingsViewerSectionTitle",
     "settingsScreenBrightnessTitle",
     "settingsScreenBrightnessDescription",
     "helpTooltip",

lib/widget/settings.dart

@@ -91,7 +91,9 @@ class _SettingsState extends State<Settings> {
                 value: _isEnableExif,
                 onChanged: (value) => _onExifSupportChanged(context, value),
               ),
-              if (platform_k.isMobile)
+              if (platform_k.isMobile) ...[
+                _buildCaption(
+                    context, L10n.of(context).settingsViewerSectionTitle),
                 SwitchListTile(
                   title: Text(L10n.of(context).settingsScreenBrightnessTitle),
                   subtitle: Text(
@@ -100,6 +102,7 @@ class _SettingsState extends State<Settings> {
                   onChanged: (value) =>
                       _onScreenBrightnessChanged(context, value),
                 ),
+              ],
               _buildCaption(
                   context, L10n.of(context).settingsAboutSectionTitle),
               ListTile(