295933aadc
The current approach for custom titlebar uses an overlay of a frameless popup window at the position of the titlebar area. This involves synchronizing the window state, position and size of the popup window with the original window. Also, the drawing of rounded edges needs to be done manually with the old approach. This patch adds the titlebar as a real child to the original window, so that the window manager takes care of the synchronization and clipping process. Fixes: QTBUG-135643 Fixes: QTBUG-133943 Fixes: QTBUG-133946 Pick-to: 6.10 6.9 Change-Id: I1770580a1c306074f41a7ff64c1d525c93918480 Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>