diff --git a/scripts/linux/headless-run.sh b/scripts/linux/headless-run.sh
index 001338db00b4..befbe32c481a 100755
--- a/scripts/linux/headless-run.sh
+++ b/scripts/linux/headless-run.sh
@@ -9,6 +9,7 @@
 #      FILES_SANDBOX_SEED (optional script run as "script <sandbox-home>" after the default sample content is created),
 #      FILES_HEADLESS_WM (optional window manager command to run on the private display, e.g. "kwin_x11"; default none),
 #      FILES_EXEC (path to a packaged launcher, e.g. Files-x86_64.AppImage or packaging/linux/files; run instead of "dotnet Files.dll"),
+#      FILES_HEADLESS_XFT_DPI (optional Xft.dpi for the private display, e.g. 144 = 1.5x), UNO_DISPLAY_SCALE_OVERRIDE (passed through),
 #      FILES_BIN (default src/Files.App/bin/Debug/net10.0-desktop), XVFB_SIZE (default 1600x1000).
 set -euo pipefail
 
@@ -60,6 +61,10 @@ if [[ -n "${FILES_HEADLESS_WM:-}" ]]; then
 	sleep 3
 fi
 
+# Optional HiDPI test: FILES_HEADLESS_XFT_DPI=120 writes Xft.dpi into the private display's X resources (Uno derives the scale from it);
+# UNO_DISPLAY_SCALE_OVERRIDE=1.5 is passed through to the app as is.
+[[ -n "${FILES_HEADLESS_XFT_DPI:-}" ]] && echo "Xft.dpi: ${FILES_HEADLESS_XFT_DPI}" | DISPLAY=":$display" xrdb -merge
+
 shot() {
 	ffmpeg -loglevel error -y -f x11grab -video_size "$size" -i ":$display" -frames:v 1 "$outdir/$1.png"
 	echo "screenshot: $outdir/$1.png"
diff --git a/src/Files.App/Data/Contracts/IAppearanceSettingsService.cs b/src/Files.App/Data/Contracts/IAppearanceSettingsService.cs
index eec23d241fa7..ef32360dfcc8 100644
--- a/src/Files.App/Data/Contracts/IAppearanceSettingsService.cs
+++ b/src/Files.App/Data/Contracts/IAppearanceSettingsService.cs
@@ -102,6 +102,11 @@ public interface IAppearanceSettingsService : IBaseSettingsService, INotifyPrope
 		/// </summary>
 		bool ShowToolbar { get; set; }
 
+		/// <summary>
+		/// Gets or sets a value whether the Sort and Layout toolbar buttons show a text label next to the icon.
+		/// </summary>
+		bool ShowToolbarSortViewLabels { get; set; }
+
 		/// <summary>
 		/// Gets or sets a value whether the status bar should be displayed.
 		/// </summary>
diff --git a/src/Files.App/Helpers/Application/AppToastNotificationHelper.cs b/src/Files.App/Helpers/Application/AppToastNotificationHelper.cs
index a73201c093bd..3bfb070c4e06 100644
--- a/src/Files.App/Helpers/Application/AppToastNotificationHelper.cs
+++ b/src/Files.App/Helpers/Application/AppToastNotificationHelper.cs
@@ -31,7 +31,11 @@ public static void ShowDriveEjectToast()
 			var toastContent = new AppNotificationBuilder()
 				.AddText(Strings.EjectNotificationHeader.GetLocalizedResource())
 				.AddText(Strings.EjectNotificationBody.GetLocalizedResource())
-				.SetAttributionText("SettingsAboutAppName".GetLocalizedResource())
+#if WINDOWS
+				.SetAttributionText("Files")
+#else
+				.SetAttributionText(Strings.LinuxAppDisplayName.GetLocalizedResource())
+#endif
 				.BuildNotification();
 			AppNotificationManager.Default.Show(toastContent);
 		}
diff --git a/src/Files.App/Platforms/Desktop/Program.cs b/src/Files.App/Platforms/Desktop/Program.cs
index 5243019ea026..1e4cb3106c8d 100644
--- a/src/Files.App/Platforms/Desktop/Program.cs
+++ b/src/Files.App/Platforms/Desktop/Program.cs
@@ -44,6 +44,9 @@ public static int Main(string[] args)
 
 			LaunchArguments = args;
 
+			// Uno reads Xft.dpi itself; this covers sessions that only export GDK/Qt scale variables
+			Files.Platform.Linux.Windowing.DisplayScaleResolver.ApplyToProcess();
+
 			// Single instance: D-Bus name (socket fallback). A second launch forwards its arguments to the running instance and exits.
 			// FILES_NO_SINGLE_INSTANCE=1 skips this (for running several instances side by side while developing).
 			var noSingleInstance = Environment.GetEnvironmentVariable("FILES_NO_SINGLE_INSTANCE") == "1";
diff --git a/src/Files.App/Platforms/Desktop/WindowEx.cs b/src/Files.App/Platforms/Desktop/WindowEx.cs
index d9a0430c83e7..2620a7cd8548 100644
--- a/src/Files.App/Platforms/Desktop/WindowEx.cs
+++ b/src/Files.App/Platforms/Desktop/WindowEx.cs
@@ -89,15 +89,17 @@ private void AppWindow_Changed(AppWindow sender, AppWindowChangedEventArgs args)
 		}
 
 		/// <summary>
-		/// Sizes the window to 80% of the primary work area (at most 1280x800 scaled up to 1600x1000 on big screens), centered.
+		/// Sizes the window to 80% of the primary work area (capped at 1600x1000 logical pixels), centered.
 		/// </summary>
 		private void ApplyDefaultSize()
 		{
 			try
 			{
 				var work = DisplayArea.Primary.WorkArea;
-				var width = Math.Clamp((int)(work.Width * 0.8), Math.Min(MinWidth, work.Width), 1600);
-				var height = Math.Clamp((int)(work.Height * 0.8), Math.Min(MinHeight, work.Height), 1000);
+				// AppWindow sizes are physical pixels; the caps are logical
+				var scale = Files.Platform.Linux.Windowing.DisplayScaleResolver.GetEffectiveScale();
+				var width = Math.Clamp((int)(work.Width * 0.8), Math.Min((int)(MinWidth * scale), work.Width), (int)(1600 * scale));
+				var height = Math.Clamp((int)(work.Height * 0.8), Math.Min((int)(MinHeight * scale), work.Height), (int)(1000 * scale));
 				AppWindow.Resize(new Windows.Graphics.SizeInt32 { Width = width, Height = height });
 				AppWindow.Move(new Windows.Graphics.PointInt32 { X = work.X + (work.Width - width) / 2, Y = work.Y + (work.Height - height) / 2 });
 			}
diff --git a/src/Files.App/Services/Settings/AppearanceSettingsService.cs b/src/Files.App/Services/Settings/AppearanceSettingsService.cs
index cedf2d48b5dd..30fecabb3f81 100644
--- a/src/Files.App/Services/Settings/AppearanceSettingsService.cs
+++ b/src/Files.App/Services/Settings/AppearanceSettingsService.cs
@@ -142,6 +142,13 @@ public bool ShowToolbar
 			set => Set(value);
 		}
 
+		/// <inheritdoc/>
+		public bool ShowToolbarSortViewLabels
+		{
+			get => Get(true);
+			set => Set(value);
+		}
+
 		/// <inheritdoc/>
 		public bool ShowStatusBar
 		{
diff --git a/src/Files.App/Strings/en-US/Resources.resw b/src/Files.App/Strings/en-US/Resources.resw
index d91255a55186..579b34890061 100644
--- a/src/Files.App/Strings/en-US/Resources.resw
+++ b/src/Files.App/Strings/en-US/Resources.resw
@@ -4993,6 +4993,27 @@
   <data name="LinuxFileSystemRoot" xml:space="preserve">
     <value>File System</value>
   </data>
+  <data name="ToggleSidebarPane" xml:space="preserve">
+    <value>Toggle sidebar</value>
+  </data>
+  <data name="StatusCenterToggleDetails" xml:space="preserve">
+    <value>Show or hide details</value>
+  </data>
+  <data name="ShowToolbarSortViewLabels" xml:space="preserve">
+    <value>Show labels on the Sort and Layout buttons</value>
+  </data>
+  <data name="Error" xml:space="preserve">
+    <value>Error</value>
+  </data>
+  <data name="FolderItemAutomation" xml:space="preserve">
+    <value>Folder</value>
+  </data>
+  <data name="CommitsNumber" xml:space="preserve">
+    <value>Commits: {0}</value>
+  </data>
+  <data name="StatusCenter_PrepareInProgress" xml:space="preserve">
+    <value>Preparing...</value>
+  </data>
   <data name="LinuxServiceMenuConfirmationText" xml:space="preserve">
     <value>This service-menu action will run the command shown below on your selection. Only run actions from sources you trust.</value>
   </data>
diff --git a/src/Files.App/Strings/fil-PH/Resources.resw b/src/Files.App/Strings/fil-PH/Resources.resw
index b601d123b47a..283ddddf4fcb 100644
--- a/src/Files.App/Strings/fil-PH/Resources.resw
+++ b/src/Files.App/Strings/fil-PH/Resources.resw
@@ -117,18 +117,12 @@
   <resheader name="writer">
     <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
   </resheader>
-  <data name="NewWindow" xml:space="preserve">
-    <value/>
-  </data>
   <data name="CopyPath" xml:space="preserve">
     <value>Kopyahin ang daan</value>
   </data>
   <data name="CopyItemPath" xml:space="preserve">
     <value>Kopyahin ang Path</value>
   </data>
-  <data name="CopyPathWithQuotes" xml:space="preserve">
-    <value/>
-  </data>
   <data name="CopyItemPathWithQuotes" xml:space="preserve">
     <value>Kopyahin ang path ng item kasama ang quotes</value>
   </data>
@@ -168,12 +162,6 @@
   <data name="SelectAll" xml:space="preserve">
     <value>Piliin lahat</value>
   </data>
-  <data name="InvertSelection" xml:space="preserve">
-    <value/>
-  </data>
-  <data name="ClearSelection" xml:space="preserve">
-    <value/>
-  </data>
   <data name="PropertiesModified.Text" xml:space="preserve">
     <value>Nabago:</value>
   </data>
@@ -309,9 +297,6 @@
   <data name="Delete" xml:space="preserve">
     <value>Burahin</value>
   </data>
-  <data name="PinFolderToSidebar" xml:space="preserve">
-    <value/>
-  </data>
   <data name="WelcomeDialogTitle" xml:space="preserve">
     <value>Welcome to Files!</value>
   </data>
diff --git a/src/Files.App/Strings/hi-IN/Resources.resw b/src/Files.App/Strings/hi-IN/Resources.resw
index 9335f5c36e46..96a06018eb09 100644
--- a/src/Files.App/Strings/hi-IN/Resources.resw
+++ b/src/Files.App/Strings/hi-IN/Resources.resw
@@ -126,9 +126,6 @@
   <data name="CopyItemPath" xml:space="preserve">
     <value>Copy item path</value>
   </data>
-  <data name="CopyPathWithQuotes" xml:space="preserve">
-    <value/>
-  </data>
   <data name="CopyItemPathWithQuotes" xml:space="preserve">
     <value>Copy selected item path with quotes</value>
   </data>
diff --git a/src/Files.App/Strings/id-ID/Resources.resw b/src/Files.App/Strings/id-ID/Resources.resw
index 1c66d6537669..cd5495910994 100644
--- a/src/Files.App/Strings/id-ID/Resources.resw
+++ b/src/Files.App/Strings/id-ID/Resources.resw
@@ -3297,9 +3297,6 @@
   <data name="OpenProperties" xml:space="preserve">
     <value>Properti</value>
   </data>
-  <data name="OpenClassicProperties" xml:space="preserve">
-    <value/>
-  </data>
   <data name="OpenPropertiesDescription" xml:space="preserve">
     <value>Buka jendela properti</value>
   </data>
diff --git a/src/Files.App/Styles/ToolbarButtonStyle.xaml b/src/Files.App/Styles/ToolbarButtonStyle.xaml
index fd6432c663f3..cc8607125428 100644
--- a/src/Files.App/Styles/ToolbarButtonStyle.xaml
+++ b/src/Files.App/Styles/ToolbarButtonStyle.xaml
@@ -13,7 +13,7 @@
 		<Setter Property="FontWeight" Value="Normal" />
 		<Setter Property="Width" Value="68" />
 		<Setter Property="UseSystemFocusVisuals" Value="{StaticResource UseSystemFocusVisuals}" />
-		<Setter Property="FocusVisualMargin" Value="-3" />
+		<Setter Property="FocusVisualMargin" Value="0" />
 		<Setter Property="AllowFocusOnInteraction" Value="False" />
 		<Setter Property="CornerRadius" Value="{ThemeResource ControlCornerRadius}" />
 		<Setter Property="KeyboardAcceleratorPlacementMode" Value="Hidden" />
diff --git a/src/Files.App/UserControls/NavigationToolbar.xaml b/src/Files.App/UserControls/NavigationToolbar.xaml
index 5814143d22d1..ab7b608d2fce 100644
--- a/src/Files.App/UserControls/NavigationToolbar.xaml
+++ b/src/Files.App/UserControls/NavigationToolbar.xaml
@@ -101,7 +101,7 @@
 				Height="32"
 				Padding="0"
 				x:Load="{x:Bind IsSidebarPaneOpenToggleButtonVisible, Mode=OneWay}"
-				AutomationProperties.Name="ToggleSidebarPane"
+				AutomationProperties.Name="{helpers:ResourceString Key=ToggleSidebarPane}"
 				Background="Transparent"
 				BorderBrush="Transparent"
 				Click="SidebarPaneToggleButton_Click"
@@ -148,6 +148,7 @@
 
 			<Button
 				x:Name="FlyoutButton"
+				AutomationProperties.Name="{helpers:ResourceString Key=SeeMore}"
 				LosingFocus="NavigationButtonOverflowFlyoutButton_LosingFocus"
 				Style="{StaticResource AddressToolbarButtonStyle}"
 				ToolTipService.ToolTip="{helpers:ResourceString Key=SeeMore}"
diff --git a/src/Files.App/UserControls/StatusCenter/StatusCenter.xaml b/src/Files.App/UserControls/StatusCenter/StatusCenter.xaml
index a9174d7b4600..2b8dc04d305c 100644
--- a/src/Files.App/UserControls/StatusCenter/StatusCenter.xaml
+++ b/src/Files.App/UserControls/StatusCenter/StatusCenter.xaml
@@ -170,6 +170,7 @@
 									Height="32"
 									Padding="0"
 									x:Load="{x:Bind IsSpeedAndProgressAvailable, Mode=OneWay}"
+									AutomationProperties.Name="{helpers:ResourceString Key=StatusCenterToggleDetails}"
 									Background="Transparent"
 									BorderBrush="Transparent"
 									IsChecked="{x:Bind IsExpanded, Mode=TwoWay}">
diff --git a/src/Files.App/UserControls/Toolbar.xaml b/src/Files.App/UserControls/Toolbar.xaml
index 0bf8e5d46d28..f6427eef0f21 100644
--- a/src/Files.App/UserControls/Toolbar.xaml
+++ b/src/Files.App/UserControls/Toolbar.xaml
@@ -160,7 +160,7 @@
 				AccessKeyInvoked="AppBarButton_AccessKeyInvoked"
 				AutomationProperties.Name="{helpers:ResourceString Key=Sort}"
 				Label="{helpers:ResourceString Key=Sort}"
-				LabelPosition="Collapsed"
+				LabelPosition="Default"
 				Style="{StaticResource ToolBarAppBarButtonFlyoutStyle}"
 				ToolTipService.ToolTip="{helpers:ResourceString Key=Sort}">
 
@@ -271,7 +271,7 @@
 				AccessKeyInvoked="AppBarButton_AccessKeyInvoked"
 				AutomationProperties.Name="{helpers:ResourceString Key=Layout}"
 				Label="{helpers:ResourceString Key=Layout}"
-				LabelPosition="Collapsed"
+				LabelPosition="Default"
 				Style="{StaticResource ToolBarAppBarButtonFlyoutStyle}"
 				ToolTipService.ToolTip="{helpers:ResourceString Key=Layout}">
 
diff --git a/src/Files.App/UserControls/Toolbar.xaml.cs b/src/Files.App/UserControls/Toolbar.xaml.cs
index 40d2ced7bbeb..970e48a9a394 100644
--- a/src/Files.App/UserControls/Toolbar.xaml.cs
+++ b/src/Files.App/UserControls/Toolbar.xaml.cs
@@ -50,6 +50,7 @@ private void Toolbar_Loaded(object sender, RoutedEventArgs e)
 		{
 			App.AppModel.PropertyChanged += AppModel_PropertyChanged;
 			foreach (var cmd in Commands) cmd.PropertyChanged += Command_PropertyChanged;
+			ApplySortViewLabels();
 			RequestToolbarRefresh(true);
 			UserSettingsService.AppearanceSettingsService.PropertyChanged += AppearanceSettings_PropertyChanged;
 		}
@@ -158,6 +159,18 @@ private void AppearanceSettings_PropertyChanged(object? sender, PropertyChangedE
 		{
 			if (e.PropertyName is nameof(IAppearanceSettingsService.CustomToolbarItems))
 				RequestToolbarRefresh(true);
+			else if (e.PropertyName is nameof(IAppearanceSettingsService.ShowToolbarSortViewLabels))
+				DispatcherQueue.TryEnqueue(ApplySortViewLabels);
+		}
+
+		private void ApplySortViewLabels()
+		{
+			var position = UserSettingsService.AppearanceSettingsService.ShowToolbarSortViewLabels
+				? CommandBarLabelPosition.Default
+				: CommandBarLabelPosition.Collapsed;
+
+			ArrangementOptions.LabelPosition = position;
+			LayoutOptionsButton.LabelPosition = position;
 		}
 
 		private async void EditTagsMenu_TagsChanged(object? sender, EventArgs e)
diff --git a/src/Files.App/ViewModels/Settings/AppearanceViewModel.cs b/src/Files.App/ViewModels/Settings/AppearanceViewModel.cs
index b352f5fffef5..1528be44d190 100644
--- a/src/Files.App/ViewModels/Settings/AppearanceViewModel.cs
+++ b/src/Files.App/ViewModels/Settings/AppearanceViewModel.cs
@@ -365,6 +365,20 @@ public bool ShowToolbar
 			}
 		}
 
+		public bool ShowToolbarSortViewLabels
+		{
+			get => UserSettingsService.AppearanceSettingsService.ShowToolbarSortViewLabels;
+			set
+			{
+				if (value != UserSettingsService.AppearanceSettingsService.ShowToolbarSortViewLabels)
+				{
+					UserSettingsService.AppearanceSettingsService.ShowToolbarSortViewLabels = value;
+
+					OnPropertyChanged();
+				}
+			}
+		}
+
 		public bool ShowStatusBar
 		{
 			get => UserSettingsService.AppearanceSettingsService.ShowStatusBar;
diff --git a/src/Files.App/Views/Settings/AppearancePage.xaml b/src/Files.App/Views/Settings/AppearancePage.xaml
index da48b5625aa9..53e223dbaf15 100644
--- a/src/Files.App/Views/Settings/AppearancePage.xaml
+++ b/src/Files.App/Views/Settings/AppearancePage.xaml
@@ -287,6 +287,12 @@
 					IsOn="{x:Bind ViewModel.ShowToolbar, Mode=TwoWay}" />
 
 				<wctcontrols:SettingsExpander.Items>
+					<wctcontrols:SettingsCard Header="{helpers:ResourceString Key=ShowToolbarSortViewLabels}">
+						<ToggleSwitch
+							AutomationProperties.AutomationControlType="Custom"
+							AutomationProperties.Name="{helpers:ResourceString Key=ShowToolbarSortViewLabels}"
+							IsOn="{x:Bind ViewModel.ShowToolbarSortViewLabels, Mode=TwoWay}" />
+					</wctcontrols:SettingsCard>
 					<wctcontrols:SettingsCard
 						Command="{x:Bind ViewModel.CustomizeToolbarCommand, Mode=OneWay}"
 						Header="{helpers:ResourceString Key=CustomizeToolbarDescription}"
diff --git a/src/Files.Platform.Linux/Native/X11Native.cs b/src/Files.Platform.Linux/Native/X11Native.cs
index db8a94ffbf32..fb66dbf0d8cc 100644
--- a/src/Files.Platform.Linux/Native/X11Native.cs
+++ b/src/Files.Platform.Linux/Native/X11Native.cs
@@ -41,6 +41,9 @@ internal static unsafe partial class X11Native
 		[LibraryImport(LibX11)]
 		public static partial int XCloseDisplay(nint display);
 
+		[LibraryImport(LibX11)]
+		public static partial nint XResourceManagerString(nint display);
+
 		[LibraryImport(LibX11)]
 		public static partial int XConnectionNumber(nint display);
 
diff --git a/src/Files.Platform.Linux/Windowing/DisplayScaleResolver.cs b/src/Files.Platform.Linux/Windowing/DisplayScaleResolver.cs
new file mode 100644
index 000000000000..44d54f063810
--- /dev/null
+++ b/src/Files.Platform.Linux/Windowing/DisplayScaleResolver.cs
@@ -0,0 +1,161 @@
+// Copyright (c) Files Community
+// Licensed under the MIT License.
+
+using System;
+using System.Globalization;
+using System.Runtime.InteropServices;
+
+namespace Files.Platform.Linux.Windowing
+{
+	/// <summary>
+	/// Works out the display scale to hand to Uno. Uno's X11 host reads <c>Xft.dpi</c> (set by KDE and GNOME on X11) and honours
+	/// <c>UNO_DISPLAY_SCALE_OVERRIDE</c>; this fills the gap when <c>Xft.dpi</c> is absent (some XWayland sessions) from toolkit variables.
+	/// </summary>
+	public static class DisplayScaleResolver
+	{
+		public const string OverrideVariable = "UNO_DISPLAY_SCALE_OVERRIDE";
+
+		/// <summary>
+		/// Returns the value to assign to <see cref="OverrideVariable"/>, or null when Uno's own detection should be used.
+		/// </summary>
+		public static string? Resolve(Func<string, string?> getEnv, string? xResources)
+		{
+			if (!string.IsNullOrWhiteSpace(getEnv(OverrideVariable)))
+				return null;
+
+			if (ParseXftDpi(xResources) is not null)
+				return null;
+
+			// Qt multiplies the global factor by the per-screen factor
+			var global = ParseScale(getEnv("QT_SCALE_FACTOR"));
+			var screen = ParseScreenFactors(getEnv("QT_SCREEN_SCALE_FACTORS"));
+			double? scale = global is null && screen is null ? null : (global ?? 1.0) * (screen ?? 1.0);
+			scale ??= ParseScale(getEnv("GDK_SCALE"));
+
+			return scale is { } s && s > 1.0 ? Math.Min(s, 4.0).ToString("0.##", CultureInfo.InvariantCulture) : null;
+		}
+
+		/// <summary>
+		/// Returns the scale Uno will use (override variable, else Xft.dpi / 96), or 1.0 when unknown.
+		/// </summary>
+		public static double GetEffectiveScale(Func<string, string?> getEnv, string? xResources)
+		{
+			if (ParseScale(getEnv(OverrideVariable)) is { } overridden)
+				return overridden;
+
+			return ParseXftDpi(xResources) is { } dpi && dpi >= 96 ? Math.Min(dpi / 96.0, 4.0) : 1.0;
+		}
+
+		/// <summary>
+		/// Returns the Xft.dpi value from X resources (tolerating whitespace around the colon), or null.
+		/// </summary>
+		public static double? ParseXftDpi(string? xResources)
+		{
+			if (string.IsNullOrEmpty(xResources))
+				return null;
+
+			foreach (var line in xResources.Split('\n'))
+			{
+				var trimmed = line.Trim();
+				var colon = trimmed.IndexOf(':');
+				if (colon < 0)
+					continue;
+
+				var name = trimmed[..colon].TrimEnd();
+				if (!name.Equals("Xft.dpi", StringComparison.OrdinalIgnoreCase) && !name.Equals("Xft*dpi", StringComparison.OrdinalIgnoreCase))
+					continue;
+
+				if (double.TryParse(trimmed[(colon + 1)..].Trim(), NumberStyles.Float, CultureInfo.InvariantCulture, out var dpi) && dpi > 0)
+					return dpi;
+			}
+
+			return null;
+		}
+
+		public static bool HasXftDpi(string? xResources) => ParseXftDpi(xResources) is not null;
+
+		private static double? ParseScale(string? value)
+		{
+			if (!double.TryParse(value, NumberStyles.Float, CultureInfo.InvariantCulture, out var scale))
+				return null;
+
+			return scale is >= 1.0 and <= 4.0 ? scale : null;
+		}
+
+		private static double? ParseScreenFactors(string? value)
+		{
+			if (string.IsNullOrWhiteSpace(value))
+				return null;
+
+			foreach (var entry in value.Split(';', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries))
+			{
+				var eq = entry.IndexOf('=');
+				if (ParseScale(eq >= 0 ? entry[(eq + 1)..] : entry) is { } scale)
+					return scale;
+			}
+
+			return null;
+		}
+
+		/// <summary>
+		/// Returns the effective scale for the current process; call after <see cref="ApplyToProcess"/>.
+		/// </summary>
+		public static double GetEffectiveScale()
+		{
+			if (!OperatingSystem.IsLinux())
+				return 1.0;
+
+			try
+			{
+				return GetEffectiveScale(Environment.GetEnvironmentVariable, ReadXResources());
+			}
+			catch (Exception)
+			{
+				return 1.0;
+			}
+		}
+
+
+		/// <summary>
+		/// Applies <see cref="Resolve"/> to the process environment. Call before the Uno host starts.
+		/// </summary>
+		public static void ApplyToProcess()
+		{
+			if (!OperatingSystem.IsLinux())
+				return;
+
+			string? resolved;
+			try
+			{
+				resolved = Resolve(Environment.GetEnvironmentVariable, ReadXResources());
+			}
+			catch (Exception)
+			{
+				// Scale detection must never block startup
+				return;
+			}
+
+			if (resolved is not null)
+				Environment.SetEnvironmentVariable(OverrideVariable, resolved);
+		}
+
+		private static string? ReadXResources()
+		{
+			if (string.IsNullOrEmpty(Environment.GetEnvironmentVariable("DISPLAY")))
+				return null;
+
+			var display = Native.X11Native.XOpenDisplay(0);
+			if (display == 0)
+				return null;
+
+			try
+			{
+				return Marshal.PtrToStringUTF8(Native.X11Native.XResourceManagerString(display));
+			}
+			finally
+			{
+				Native.X11Native.XCloseDisplay(display);
+			}
+		}
+	}
+}
diff --git a/tests/Files.Platform.Tests/Localization/ResourceKeyTests.cs b/tests/Files.Platform.Tests/Localization/ResourceKeyTests.cs
new file mode 100644
index 000000000000..e1f892113d06
--- /dev/null
+++ b/tests/Files.Platform.Tests/Localization/ResourceKeyTests.cs
@@ -0,0 +1,102 @@
+// Copyright (c) Files Community
+// Licensed under the MIT License.
+
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text.RegularExpressions;
+using System.Xml.Linq;
+
+namespace Files.Platform.Tests.Localization
+{
+	/// <summary>
+	/// New strings are added to en-US only; the other locales fall back to it at runtime. These checks make sure code never
+	/// asks for a key that en-US does not define (which would show an empty label in every locale).
+	/// </summary>
+	[TestClass]
+	public sealed partial class ResourceKeyTests
+	{
+		[GeneratedRegex(@"""([A-Za-z0-9_.]+)""\s*\.GetLocalizedResource\(")]
+		private static partial Regex LiteralKeyRegex();
+
+		[GeneratedRegex(@"ResourceString\s+(?:Key=)?([A-Za-z0-9_./]+)")]
+		private static partial Regex XamlKeyRegex();
+
+		[GeneratedRegex(@"\bx:Uid=""([^""]+)""")]
+		private static partial Regex UidRegex();
+
+		private static string AppDir
+		{
+			get
+			{
+				var dir = new DirectoryInfo(AppContext.BaseDirectory);
+				while (dir is not null && !File.Exists(Path.Combine(dir.FullName, "Files.slnx")))
+					dir = dir.Parent;
+
+				Assert.IsNotNull(dir, "Repository root not found");
+				return Path.Combine(dir.FullName, "src", "Files.App");
+			}
+		}
+
+		private static HashSet<string> LoadKeys(string locale)
+		{
+			var doc = XDocument.Load(Path.Combine(AppDir, "Strings", locale, "Resources.resw"));
+			return doc.Descendants("data").Select(d => (string)d.Attribute("name")!).ToHashSet(StringComparer.OrdinalIgnoreCase);
+		}
+
+		private static IEnumerable<string> SourceFiles(string pattern) =>
+			Directory.EnumerateFiles(AppDir, pattern, SearchOption.AllDirectories)
+				.Where(f => !f.EndsWith(".Windows.cs", StringComparison.Ordinal) && !f.Contains($"{Path.DirectorySeparatorChar}obj{Path.DirectorySeparatorChar}") && !f.Contains($"{Path.DirectorySeparatorChar}bin{Path.DirectorySeparatorChar}"));
+
+		[TestMethod]
+		public void LiteralKeysUsedInCode_ExistInEnUs()
+		{
+			var keys = LoadKeys("en-US");
+			var missing = SourceFiles("*.cs")
+				.SelectMany(f => LiteralKeyRegex().Matches(File.ReadAllText(f)).Select(m => (File: Path.GetFileName(f), Key: m.Groups[1].Value)))
+				.Where(x => !keys.Contains(x.Key))
+				.Select(x => $"{x.File}: {x.Key}")
+				.Distinct()
+				.ToList();
+
+			Assert.AreEqual(0, missing.Count, "Keys missing from en-US: " + string.Join(", ", missing));
+		}
+
+		[TestMethod]
+		public void XamlKeys_ExistInEnUs()
+		{
+			var keys = LoadKeys("en-US");
+			var missing = new List<string>();
+			foreach (var file in SourceFiles("*.xaml"))
+			{
+				var text = File.ReadAllText(file);
+				foreach (Match m in XamlKeyRegex().Matches(text))
+					if (!keys.Contains(m.Groups[1].Value.Replace('/', '.')))
+						missing.Add($"{Path.GetFileName(file)}: {m.Groups[1].Value}");
+
+				foreach (Match m in UidRegex().Matches(text))
+					if (!keys.Any(k => k.StartsWith(m.Groups[1].Value + ".", StringComparison.OrdinalIgnoreCase)))
+						missing.Add($"{Path.GetFileName(file)}: x:Uid {m.Groups[1].Value}");
+			}
+
+			Assert.AreEqual(0, missing.Count, "Keys missing from en-US: " + string.Join(", ", missing.Distinct()));
+		}
+
+		[TestMethod]
+		public void OtherLocales_DoNotDefineEmptyValues()
+		{
+			var offenders = new List<string>();
+			foreach (var dir in Directory.EnumerateDirectories(Path.Combine(AppDir, "Strings")))
+			{
+				var doc = XDocument.Load(Path.Combine(dir, "Resources.resw"));
+				offenders.AddRange(doc.Descendants("data")
+					.Where(d => string.IsNullOrWhiteSpace((string?)d.Element("value")))
+					.Select(d => $"{Path.GetFileName(dir)}: {(string)d.Attribute("name")!}"));
+			}
+
+			Assert.AreEqual(0, offenders.Count, "Empty translations hide the en-US fallback: " + string.Join(", ", offenders.Take(20)));
+		}
+	}
+}
diff --git a/tests/Files.Platform.Tests/Windowing/DisplayScaleResolverTests.cs b/tests/Files.Platform.Tests/Windowing/DisplayScaleResolverTests.cs
new file mode 100644
index 000000000000..b18463b04546
--- /dev/null
+++ b/tests/Files.Platform.Tests/Windowing/DisplayScaleResolverTests.cs
@@ -0,0 +1,90 @@
+// Copyright (c) Files Community
+// Licensed under the MIT License.
+
+using Files.Platform.Linux.Windowing;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System.Collections.Generic;
+
+namespace Files.Platform.Tests.Windowing
+{
+	[TestClass]
+	public sealed class DisplayScaleResolverTests
+	{
+		private static string? Resolve(string? xResources, params (string Key, string Value)[] env)
+		{
+			var map = new Dictionary<string, string>();
+			foreach (var (key, value) in env)
+				map[key] = value;
+
+			return DisplayScaleResolver.Resolve(k => map.GetValueOrDefault(k), xResources);
+		}
+
+		[TestMethod]
+		public void XftDpi_LeavesDetectionToUno()
+		{
+			Assert.IsNull(Resolve("Xft.dpi:\t144\n", ("GDK_SCALE", "2")));
+		}
+
+		[TestMethod]
+		public void ExplicitOverride_IsRespected()
+		{
+			Assert.IsNull(Resolve(null, ("UNO_DISPLAY_SCALE_OVERRIDE", "1.5"), ("GDK_SCALE", "2")));
+		}
+
+		[TestMethod]
+		public void GdkScale_UsedWithoutXftDpi()
+		{
+			Assert.AreEqual("2", Resolve("*.background: black\n", ("GDK_SCALE", "2")));
+		}
+
+		[TestMethod]
+		public void QtScaleFactor_BeatsGdkScale()
+		{
+			Assert.AreEqual("1.25", Resolve(null, ("QT_SCALE_FACTOR", "1.25"), ("GDK_SCALE", "2")));
+		}
+
+		[TestMethod]
+		public void QtScreenFactors_UsesFirstScreen()
+		{
+			Assert.AreEqual("1.5", Resolve(null, ("QT_SCREEN_SCALE_FACTORS", "DP-1=1.5;HDMI-1=1")));
+		}
+
+		[TestMethod]
+		public void InvalidOrUnitScale_ReturnsNull()
+		{
+			Assert.IsNull(Resolve(null, ("GDK_SCALE", "1")));
+			Assert.IsNull(Resolve(null, ("QT_SCALE_FACTOR", "abc")));
+			Assert.IsNull(Resolve(null, ("QT_SCALE_FACTOR", "40")));
+		}
+
+		[TestMethod]
+		public void EffectiveScale_PrefersOverrideThenXftDpi()
+		{
+			var map = new Dictionary<string, string> { ["UNO_DISPLAY_SCALE_OVERRIDE"] = "1.5" };
+			Assert.AreEqual(1.5, DisplayScaleResolver.GetEffectiveScale(k => map.GetValueOrDefault(k), "Xft.dpi:\t192\n"));
+			Assert.AreEqual(2.0, DisplayScaleResolver.GetEffectiveScale(_ => null, "Xft.dpi:\t192\n"));
+			Assert.AreEqual(1.0, DisplayScaleResolver.GetEffectiveScale(_ => null, null));
+		}
+
+		[TestMethod]
+		public void MalformedScreenFactors_DoNotThrow()
+		{
+			foreach (var value in new[] { ";", ";;", "=", "DP-1=", "DP-1=abc;", " ; ", "DP-1=0" })
+				Assert.IsNull(Resolve(null, ("QT_SCREEN_SCALE_FACTORS", value)), value);
+		}
+
+		[TestMethod]
+		public void QtFactors_AreComposed()
+		{
+			Assert.AreEqual("2", Resolve(null, ("QT_SCALE_FACTOR", "1"), ("QT_SCREEN_SCALE_FACTORS", "DP-1=2")));
+			Assert.AreEqual("3", Resolve(null, ("QT_SCALE_FACTOR", "1.5"), ("QT_SCREEN_SCALE_FACTORS", "DP-1=2")));
+		}
+
+		[TestMethod]
+		public void XftDpi_ToleratesWhitespaceBeforeColon()
+		{
+			Assert.IsNull(Resolve("Xft.dpi : 144\n", ("GDK_SCALE", "2")));
+			Assert.AreEqual(1.5, DisplayScaleResolver.GetEffectiveScale(_ => null, "  Xft.dpi\t:\t144\r\n"));
+		}
+	}
+}