diff --git a/Penumbra/Configuration.Migration.cs b/Penumbra/Configuration.Migration.cs
index a62c091b..3eca3c07 100644
--- a/Penumbra/Configuration.Migration.cs
+++ b/Penumbra/Configuration.Migration.cs
@@ -47,6 +47,15 @@ public partial class Configuration
             m.Version1To2();
             m.Version2To3();
             m.Version3To4();
+            m.Version4To5();
+        }
+
+        // Mod backup extension was changed from .zip to .pmp.
+        // Actual migration takes place in ModManager.
+        private void Version4To5()
+        {
+            Mod.Manager.MigrateModBackups = true;
+            _config.Version               = 5;
         }
 
         // SortMode was changed from an enum to a type.
diff --git a/Penumbra/Configuration.cs b/Penumbra/Configuration.cs
index 0e95a7f6..9b6381a7 100644
--- a/Penumbra/Configuration.cs
+++ b/Penumbra/Configuration.cs
@@ -8,7 +8,6 @@ using Newtonsoft.Json;
 using OtterGui;
 using OtterGui.Classes;
 using OtterGui.Filesystem;
-using OtterGui.Widgets;
 using Penumbra.Import;
 using Penumbra.Mods;
 using Penumbra.UI;
@@ -142,7 +141,7 @@ public partial class Configuration : IPluginConfiguration
     // Contains some default values or boundaries for config values.
     public static class Constants
     {
-        public const int   CurrentVersion      = 4;
+        public const int   CurrentVersion      = 5;
         public const float MaxAbsoluteSize     = 600;
         public const int   DefaultAbsoluteSize = 250;
         public const float MinAbsoluteSize     = 50;
diff --git a/Penumbra/Import/TexToolsImport.cs b/Penumbra/Import/TexToolsImport.cs
index 3dcf5d47..98c1df0b 100644
--- a/Penumbra/Import/TexToolsImport.cs
+++ b/Penumbra/Import/TexToolsImport.cs
@@ -121,7 +121,7 @@ public partial class TexToolsImporter : IDisposable
     // Puts out warnings if extension does not correspond to data.
     private DirectoryInfo VerifyVersionAndImport( FileInfo modPackFile )
     {
-        if( modPackFile.Extension is ".zip" or ".7z" or ".rar" )
+        if( modPackFile.Extension.ToLowerInvariant() is ".pmp" or ".zip" or ".7z" or ".rar" )
         {
             return HandleRegularArchive( modPackFile );
         }
diff --git a/Penumbra/Mods/Editor/ModBackup.cs b/Penumbra/Mods/Editor/ModBackup.cs
index acc9e8af..fa353fd4 100644
--- a/Penumbra/Mods/Editor/ModBackup.cs
+++ b/Penumbra/Mods/Editor/ModBackup.cs
@@ -18,10 +18,39 @@ public class ModBackup
     public ModBackup( Mod mod )
     {
         _mod   = mod;
-        Name   = mod.ModPath + ".zip";
+        Name   = _mod.ModPath + ".pmp";
         Exists = File.Exists( Name );
     }
 
+    // Migrate file extensions.
+    public static void MigrateZipToPmp(Mod.Manager manager)
+    {
+        foreach( var mod in manager )
+        {
+            var pmpName = mod.ModPath + ".pmp";
+            var zipName = mod.ModPath + ".zip";
+            if( File.Exists( zipName ) )
+            {
+                try
+                {
+                    if( !File.Exists( pmpName ) )
+                    {
+                        File.Move( zipName, pmpName );
+                    }
+                    else
+                    {
+                        File.Delete( zipName );
+                    }
+                    PluginLog.Information( $"Migrated mod backup from {zipName} to {pmpName}." );
+                }
+                catch( Exception e )
+                {
+                    PluginLog.Warning( $"Could not migrate mod backup of {mod.ModPath} from .pmp to .zip:\n{e}" );
+                }
+            }
+        }
+    }
+
     // Create a backup zip without blocking the main thread.
     public async void CreateAsync()
     {
diff --git a/Penumbra/Mods/Manager/Mod.Manager.Root.cs b/Penumbra/Mods/Manager/Mod.Manager.Root.cs
index 92a8c51e..cec734ee 100644
--- a/Penumbra/Mods/Manager/Mod.Manager.Root.cs
+++ b/Penumbra/Mods/Manager/Mod.Manager.Root.cs
@@ -99,6 +99,11 @@ public sealed partial class Mod
 
             ModDiscoveryFinished?.Invoke();
             PluginLog.Information( "Rediscovered mods." );
+
+            if( MigrateModBackups )
+            {
+                ModBackup.MigrateZipToPmp( this );
+            }
         }
     }
 }
\ No newline at end of file
diff --git a/Penumbra/Mods/Manager/Mod.Manager.cs b/Penumbra/Mods/Manager/Mod.Manager.cs
index ff800473..11f878ca 100644
--- a/Penumbra/Mods/Manager/Mod.Manager.cs
+++ b/Penumbra/Mods/Manager/Mod.Manager.cs
@@ -9,6 +9,9 @@ public sealed partial class Mod
 {
     public sealed partial class Manager : IReadOnlyList< Mod >
     {
+        // Set when reading Config and migrating from v4 to v5.
+        public static bool MigrateModBackups = false;
+
         // An easily accessible set of new mods.
         // Mods are added when they are created or imported.
         // Mods are removed when they are deleted or when they are toggled in any collection.
diff --git a/Penumbra/Penumbra.cs b/Penumbra/Penumbra.cs
index e4081ba0..fdb59a91 100644
--- a/Penumbra/Penumbra.cs
+++ b/Penumbra/Penumbra.cs
@@ -143,7 +143,7 @@ public class Penumbra : IDalamudPlugin
             Dalamud.PluginInterface.UiBuilder.Draw += _windowSystem.Draw;
 
             OtterTex.NativeDll.Initialize( Dalamud.PluginInterface.AssemblyLocation.DirectoryName );
-            PluginLog.Information( $"Loading native assembly from {OtterTex.NativeDll.Directory}." );
+            PluginLog.Information( $"Loading native OtterTex assembly from {OtterTex.NativeDll.Directory}." );
         }
         catch
         {
@@ -165,10 +165,17 @@ public class Penumbra : IDalamudPlugin
 
     private void DisposeInterface()
     {
-        Dalamud.PluginInterface.UiBuilder.Draw         -= _windowSystem.Draw;
-        Dalamud.PluginInterface.UiBuilder.OpenConfigUi -= _configWindow.Toggle;
+        if( _windowSystem != null )
+        {
+            Dalamud.PluginInterface.UiBuilder.Draw -= _windowSystem.Draw;
+        }
+
         _launchButton?.Dispose();
-        _configWindow?.Dispose();
+        if( _configWindow != null )
+        {
+            Dalamud.PluginInterface.UiBuilder.OpenConfigUi -= _configWindow.Toggle;
+            _configWindow.Dispose();
+        }
     }
 
     public bool Enable()
diff --git a/Penumbra/UI/Classes/ModFileSystemSelector.cs b/Penumbra/UI/Classes/ModFileSystemSelector.cs
index be0d838b..9b83fc67 100644
--- a/Penumbra/UI/Classes/ModFileSystemSelector.cs
+++ b/Penumbra/UI/Classes/ModFileSystemSelector.cs
@@ -200,7 +200,7 @@ public sealed partial class ModFileSystemSelector : FileSystemSelector< Mod, Mod
     private void AddImportModButton( Vector2 size )
     {
         var button = ImGuiUtil.DrawDisabledButton( FontAwesomeIcon.FileImport.ToIconString(), size,
-            "Import one or multiple mods from Tex Tools Mod Pack Files.", !Penumbra.ModManager.Valid, true );
+            "Import one or multiple mods from Tex Tools Mod Pack Files or Penumbra Mod Pack Files.", !Penumbra.ModManager.Valid, true );
         ConfigWindow.OpenTutorial( ConfigWindow.BasicTutorialSteps.ModImport );
         if( !button )
         {
@@ -213,7 +213,7 @@ public sealed partial class ModFileSystemSelector : FileSystemSelector< Mod, Mod
         _hasSetFolder = true;
 
         _fileManager.OpenFileDialog( "Import Mod Pack",
-            "Mod Packs{.ttmp,.ttmp2,.zip,.7z,.rar},TexTools Mod Packs{.ttmp,.ttmp2},Archives{.zip,.7z,.rar}", ( s, f ) =>
+            "Mod Packs{.ttmp,.ttmp2,.pmp},TexTools Mod Packs{.ttmp,.ttmp2},Penumbra Mod Packs{.pmp},Archives{.zip,.7z,.rar}", ( s, f ) =>
             {
                 if( s )
                 {