fix windows and mac

Author: DEATHB4DEFEAT

MSBuild/Launcher.DefineConstants.targets

@@ -1,5 +1,34 @@
 <Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="12.0">
   <!-- Adds to the DefineConstants to provide things such as platform-specific defines. -->
+  <PropertyGroup>
+    <OS Condition="'$(OS)' == ''">Windows_NT</OS>
+  </PropertyGroup>
+  <Choose>
+    <When Condition="'$(OS)' != 'Unix'">
+      <PropertyGroup>
+        <ActualOS>Windows</ActualOS>
+      </PropertyGroup>
+    </When>
+    <!-- Folders that *probably* only exist on MacOS and not Linux. -->
+    <When Condition="Exists('/Volumes') And Exists('/System') And Exists('/Library')" >
+      <PropertyGroup>
+        <ActualOS>MacOS</ActualOS>
+      </PropertyGroup>
+    </When>
+    <When Condition="$([MSBuild]::IsOSPlatform('FreeBSD'))">
+      <PropertyGroup>
+        <ActualOS>FreeBSD</ActualOS>
+      </PropertyGroup>
+    </When>
+    <Otherwise>
+      <PropertyGroup>
+        <ActualOS>Linux</ActualOS>
+      </PropertyGroup>
+    </Otherwise>
+  </Choose>
+  <PropertyGroup>
+    <TargetOS Condition="'$(TargetOS)' == ''">$(ActualOS)</TargetOS>
+  </PropertyGroup>
   <Choose>
     <When Condition="'$(TargetOS)' == 'Windows'">
       <PropertyGroup>

SS14.Launcher/App.xaml.cs

@@ -108,7 +108,7 @@ private void RegisterProtocol()
         Log.Information("Registering SS14 protocol handler for Windows");
         foreach (var protocol in protocols)
         {
-            var key = Registry.ClassesRoot.CreateSubKey(protocol);
+            var key = Registry.CurrentUser.CreateSubKey($@"SOFTWARE\Classes\{protocol}");
             key.SetValue(string.Empty, $"URL: {protocol}");
             key.SetValue("URL Protocol", string.Empty);