diff --git a/app/MindWork AI Studio/Pages/Plugins.razor.cs b/app/MindWork AI Studio/Pages/Plugins.razor.cs
index b563a9dc..bbed3dc6 100644
--- a/app/MindWork AI Studio/Pages/Plugins.razor.cs	
+++ b/app/MindWork AI Studio/Pages/Plugins.razor.cs	
@@ -559,7 +559,7 @@ public partial class Plugins : MSGComponentBase
         switch (archivePaths.Count)
         {
             case 0:
-                await this.MessageBus.SendWarning(new(Icons.Material.Filled.ReportProblem, string.Format(this.T("Please drop a plugin archive with the extension {0} or .zip."), PluginShareService.PLUGIN_FILE_EXTENSION)));
+                await this.MessageBus.SendWarning(new(Icons.Material.Filled.ReportProblem, string.Format(this.T("Please drop a plugin archive with the extension {0} or .zip."), PluginArchive.PLUGIN_FILE_EXTENSION)));
                 return;
 
             case > 1:
diff --git a/app/MindWork AI Studio/Tools/PluginSystem/PluginArchive.cs b/app/MindWork AI Studio/Tools/PluginSystem/PluginArchive.cs
index 4f281f21..4db08c72 100644
--- a/app/MindWork AI Studio/Tools/PluginSystem/PluginArchive.cs	
+++ b/app/MindWork AI Studio/Tools/PluginSystem/PluginArchive.cs	
@@ -4,6 +4,16 @@ namespace AIStudio.Tools.PluginSystem;
 
 public static class PluginArchive
 {
+    /// <summary>
+    /// The file extension of plugin archives.
+    /// </summary>
+    /// <remarks>
+    /// Keep in sync with SHARE_FILE_EXTENSION in runtime/src/share_sheet.rs: the runtime only hands
+    /// archives with this extension to the native share sheet.
+    /// </remarks>
+    public const string PLUGIN_FILE_EXTENSION = ".mwplugin";
+
+
     // Compatibility shim for Windows-created ZIPs with backslashes in entry names (dotnet/runtime#27620);
     // remove after dotnet/runtime#27620 and #41914 are fixed.
     // See documentation/compatibility-shims/2026-07-plugin-archive-zip-backslashes.md.
diff --git a/app/MindWork AI Studio/Tools/Rust/FileTypes.cs b/app/MindWork AI Studio/Tools/Rust/FileTypes.cs
index 9bc7ab59..038833f0 100644
--- a/app/MindWork AI Studio/Tools/Rust/FileTypes.cs	
+++ b/app/MindWork AI Studio/Tools/Rust/FileTypes.cs	
@@ -1,5 +1,4 @@
 using AIStudio.Tools.PluginSystem;
-using AIStudio.Tools.Services;
 
 // ReSharper disable MemberCanBePrivate.Global
 
@@ -83,7 +82,7 @@ public static class FileTypes
     // Other standalone types
     public static readonly FileTypeFilter CERTIFICATE_BUNDLE = FileTypeFilter.Leaf(TB("Certificate bundle"), "pem", "crt", "cer");
     public static readonly FileTypeFilter EXECUTABLES = FileTypeFilter.Leaf(TB("Executable"), "exe", "app", "bin", "appimage");
-    public static readonly FileTypeFilter PLUGIN_ARCHIVE = FileTypeFilter.Leaf(TB("Plugin archive"), PluginShareService.PLUGIN_FILE_EXTENSION.TrimStart('.'), "zip");
+    public static readonly FileTypeFilter PLUGIN_ARCHIVE = FileTypeFilter.Leaf(TB("Plugin archive"), PluginArchive.PLUGIN_FILE_EXTENSION.TrimStart('.'), "zip");
     
     public static FileTypeFilter? AsOneFileType(params FileTypeFilter[]? types)
     {
diff --git a/app/MindWork AI Studio/Tools/Services/PluginShareService.cs b/app/MindWork AI Studio/Tools/Services/PluginShareService.cs
index a56c1886..9b7b2983 100644
--- a/app/MindWork AI Studio/Tools/Services/PluginShareService.cs	
+++ b/app/MindWork AI Studio/Tools/Services/PluginShareService.cs	
@@ -11,12 +11,6 @@ public sealed class PluginShareService(NativeShareService nativeShareService, Ru
     
     private static string TB(string fallbackEN) => I18N.I.T(fallbackEN, typeof(PluginShareService).Namespace, nameof(PluginShareService));
 
-    /// <remarks>
-    /// Keep in sync with SHARE_FILE_EXTENSION in runtime/src/share_sheet.rs: the runtime only hands
-    /// archives with this extension to the native share sheet.
-    /// </remarks>
-    public const string PLUGIN_FILE_EXTENSION = ".mwplugin";
-
     private const string PLUGIN_FILE_NAME = "plugin.lua";
 
     /// <remarks>
@@ -69,7 +63,7 @@ public sealed class PluginShareService(NativeShareService nativeShareService, Ru
     /// <returns>The share result, including the chosen archive path when successful.</returns>
     private async Task<PluginShareResult> ExportAsync(IAvailablePlugin plugin, string pluginRoot, CancellationToken token)
     {
-        var suggestedFileName = $"{CreateSafeFileNamePrefix(plugin.Name)}{PLUGIN_FILE_EXTENSION}";
+        var suggestedFileName = $"{CreateSafeFileNamePrefix(plugin.Name)}{PluginArchive.PLUGIN_FILE_EXTENSION}";
         var saveResponse = await rustService.SaveFile(TB("Export plugin archive"), [FileTypes.PLUGIN_ARCHIVE], suggestedFileName);
         if (saveResponse.UserCancelled)
             return new(false, plugin.Name, string.Empty, string.Empty, true);
@@ -116,7 +110,7 @@ public sealed class PluginShareService(NativeShareService nativeShareService, Ru
     private async Task<PluginShareResult> ShareViaNativeSheetAsync(IAvailablePlugin plugin, string pluginRoot, CancellationToken token)
     {
         var archiveDirectory = Path.Join(Path.GetTempPath(), TEMPORARY_ARCHIVE_DIRECTORY);
-        var archivePath = Path.Join(archiveDirectory, $"{CreateSafeFileNamePrefix(plugin.Name)}-{plugin.Id:N}-{Guid.NewGuid():N}{PLUGIN_FILE_EXTENSION}");
+        var archivePath = Path.Join(archiveDirectory, $"{CreateSafeFileNamePrefix(plugin.Name)}-{plugin.Id:N}-{Guid.NewGuid():N}{PluginArchive.PLUGIN_FILE_EXTENSION}");
 
         try
         {
@@ -193,7 +187,7 @@ public sealed class PluginShareService(NativeShareService nativeShareService, Ru
     private void CleanUpExpiredArchives(string archiveDirectory)
     {
         var expiry = DateTime.UtcNow.AddHours(-TEMPORARY_ARCHIVE_RETENTION_HOURS);
-        foreach (var archivePath in Directory.EnumerateFiles(archiveDirectory, $"*{PLUGIN_FILE_EXTENSION}", SearchOption.TopDirectoryOnly))
+        foreach (var archivePath in Directory.EnumerateFiles(archiveDirectory, $"*{PluginArchive.PLUGIN_FILE_EXTENSION}", SearchOption.TopDirectoryOnly))
         {
             try
             {