Using QT5 with IDE form designer

[Fred vS]

An easier solution that works now, probably for some time to come, is to use XCB, our Qt5 and Qt6 apps will accept a command line parameter, "-platform xcb"  (single dash and no '=') and that will make it use the older x11 protocols, windows can report their positions and be restored to those positions. Faster screen i/o too. On some DEs, it fixes SystemTray problems. No code changes.

Note that the last libX11.so use xcb library in nearly all his methods now.
(Okay, this has nothing to do with the topic, it's just to defuse a libX11.so vs libxcb.so war  ).

[dbannon]

Note that platform xcb won't work if xcb libs aren't installed. Havent tested on distro which have XWayland only, how it redirects (if) from xcb to XWayland.

I have not found, yet, a distro without it installed by default. Its in Debian Unstable, due for release in 2028 (?) but obviously could be removed before then. Would seem a good idea to list it as a dependency just in case...

The question might be will Qt7 know how to switch to xcb ?

Davo

[Fred vS]

The question might be will Qt7 know how to switch to xcb ?

xcb (https://xcb.freedesktop.org/) is part of freedesktop.org, like Wayland, XWayland and X11.
Of course if XWayland is installed, libxcb /libX11 are installed too, they are the client interface for XWayland/X11.  And if Qt7 is using libX11, no problem, libX11 methods use xcb now.