Qt: NativeThemeStylesheetNeedsUpdate() should not apply to Fusion

src/duckstation-qt/qthost.h

@@ -354,6 +354,9 @@ bool IsStyleSheetApplicationTheme();
 /// Sets the icon theme, based on the current style (light/dark).
 void UpdateThemeOnStyleChange();
 
+/// Returns true if using the native theme and it has stylesheet overrides.
+bool NativeThemeStylesheetNeedsUpdate();
+
 /// Sets batch mode (exit after game shutdown).
 bool InBatchMode();
 

src/duckstation-qt/qtthemes.cpp

@@ -18,7 +18,6 @@ namespace QtHost {
 static void SetThemeAttributes(bool is_stylesheet_theme, bool is_variable_color_theme, bool is_dark_theme);
 static void SetStyleFromSettings();
 static QString GetNativeThemeStylesheet();
-static bool NativeThemeStylesheetNeedsUpdate();
 
 namespace {
 struct State
@@ -561,7 +560,8 @@ bool QtHost::NativeThemeStylesheetNeedsUpdate()
 {
 #ifdef __APPLE__
   // See below, only used on MacOS.
-  return s_state.is_variable_color_theme;
+  // objectName() is empty after applying stylesheet.
+  return (s_state.is_variable_color_theme && QApplication::style()->objectName().isEmpty());
 #else
   return false;
 #endif