Desktop App Toolkit uses GLib as the D-Bus library for quite long time, but GLib is not only a D-Bus library, it's more a basic library providing native Linux APIs implementing various specs. The situation right now is that DESKTOP_APP_DISABLE_DBUS_INTEGRATION disables not only D-Bus code but all the native API integration such as MIME handling or .desktop file parsing. In other words, the option disables native Linux APIs on Linux what is absurd and doesn't have any sense.
qt5ct is removed since internal gtk integration is good enough
Removed the ability to override path to qtwayland client headers since that hack is no longer used
QXdgDesktopPortalThemePlugin is no longer linked since custom xdg-desktop-portal dialog implementation is present
