thirdparty-vanilla: add UnitXP SP3 skin

modules/thirdparty-vanilla.lua

@@ -1220,4 +1220,19 @@ pfUI:RegisterModule("thirdparty-vanilla", "vanilla", function()
     -- disable macro extenders setting
     MacroExtender_Options.Inventory = nil
   end)
+
+  -- UnitXP SP3 compatibility
+  -- https://github.com/allfoxwy/UnitXP_SP3
+  HookAddonOrVariable("UnitXP_SP3_Addon", function()
+    -- skin main menu button
+    SkinButton(GameMenuButtonXPSP3)
+    -- skin UnitXP SP3 window and elements
+    StripTextures(xpsp3Frame)
+    CreateBackdrop(xpsp3Frame)
+    SkinCheckbox(xpsp3_checkButton_modernNameplate)
+    SkinCheckbox(xpsp3_checkButton_notify_flashTaskbarIcon)
+    SkinCheckbox(xpsp3_checkButton_notify_playSystemDefaultSound)
+    SkinButton(xpsp3_button_close)
+  end)
+    
 end)