Dim disabled items in context menus (#4423)

src/singletons/Theme.cpp

@@ -212,6 +212,14 @@ void Theme::parseFrom(const QJsonObject &root)
         (this->isLightTheme() ? "#68B1FF"
                               : this->tabs.selected.backgrounds.regular.name());
 
+    this->window.contextMenuStyleSheet =
+        QStringLiteral("QMenu { background: %1; border: %2; color: %3; "
+                       "selection-background-color: %2; } "
+                       "QMenu::item:disabled { color: #8c7f7f; }")
+            .arg(splits.input.background.name(QColor::HexArgb),
+                 tabs.selected.backgrounds.regular.name(QColor::HexArgb),
+                 tabs.selected.text.name(QColor::HexArgb));
+
     // Usercard buttons
     if (this->isLightTheme())
     {

src/singletons/Theme.hpp

@@ -39,6 +39,8 @@ public:
     struct {
         QColor background;
         QColor text;
+
+        QString contextMenuStyleSheet;
     } window;
 
     /// TABS