Fix hovered menu icons vanishing in the Windows 11 style

A highlighted menu item's icon was redrawn in the highlighted-text
color, white in most palettes, for the highlight bar Fusion draws. The
Windows 11 style draws a pale fill and the normal text color instead,
so the white icon disappeared on light colors (issue #1591). Leave the
icon to the ordinary hover tint there, except in high contrast, where
that style does draw a highlight bar.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

sources/qetstyle.cpp

@@ -21,6 +21,7 @@
 #include <QImage>
 #include <QPainter>
 #include <QPixmap>
+#include <QStyleHints>
 #include <QStyleOption>
 #include <QWidget>
 
@@ -136,6 +137,24 @@ QIcon QETStyle::menuIcon(const QIcon &icon, const QPalette &palette, int size, q
 	return result;
 }
 
+/**
+	@brief QETStyle::hasMenuHighlightBar
+	False for the Windows 11 style outside high contrast: it marks a
+	highlighted menu item with a pale fill and keeps the normal text
+	color, so an icon in the highlighted-text color would vanish on it
+	(issue #1591).
+*/
+bool QETStyle::hasMenuHighlightBar() const
+{
+	if (objectName().compare(QLatin1String("windows11"), Qt::CaseInsensitive) != 0)
+		return true;
+#if QT_VERSION >= QT_VERSION_CHECK(6, 5, 0)
+	return QGuiApplication::styleHints()->colorScheme() == Qt::ColorScheme::Unknown;
+#else
+	return true;
+#endif
+}
+
 /**
 	@brief QETStyle::drawControl
 	CE_MenuItem with an icon and a highlight: swap the icon for menuIcon()
@@ -147,7 +166,7 @@ void QETStyle::drawControl(ControlElement element,
                            QPainter *painter,
                            const QWidget *widget) const
 {
-	if (element == CE_MenuItem)
+	if (element == CE_MenuItem && hasMenuHighlightBar())
 	{
 		const auto *item = qstyleoption_cast<const QStyleOptionMenuItem *>(option);
 		if (item && !item->icon.isNull()

sources/qetstyle.h

@@ -41,6 +41,8 @@
 	vanish. The generated pixmap is cached per icon and cannot tell a
 	menu from a toolbar, so drawControl(CE_MenuItem) hands the base style
 	an icon whose Active pixmap is the icon in the highlighted-text color.
+	The Windows 11 style draws no highlight bar (see hasMenuHighlightBar()),
+	so its highlighted menu items keep the hover tint.
 */
 class QETStyle : public QProxyStyle
 {
@@ -66,6 +68,7 @@ class QETStyle : public QProxyStyle
 		static QPixmap tinted(const QPixmap &pixmap, const QColor &color);
 
 	private:
+		bool hasMenuHighlightBar() const;
 		QIcon menuIcon(const QIcon &icon, const QPalette &palette, int size, qreal dpr) const;
 		mutable QHash<QString, QIcon> menu_icons_;
 };