[Linux] "Cancel account setup" dialog not modal

[fmoc]

Pre-submission Checks

• I checked for similar issues, but could not find any. I also checked the closed issues. I could not contribute additional information to any existing issue.
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Describe the bug

When canceling the account setup, a dialog is shown asking for confirmation. It's possible to click on the setup wizard again, which thereafter effectively hides the confirmation dialog. To be able to access it again, one has to move it out of the way. Clicking on the item in the taskbar or using the systray to show the UI do not yield a different result.

Expected behavior

The cancel dialog must be a mandatory modal dialog that is always shown above all other windows.

Steps to reproduce the issue

No response

Screenshots

Logs

No response

Client version number

Build made from latest master. Should affect the current dailies, too.

Desktop environment (Linux only)

No response

Client package version and origin (Linux only)

No response

Installation path (Windows only)

No response

Server information

No response

Additional context

No response

[TheOneRing]

Can't reproduce on Windows, or mac.

[fmoc]

Smells like a Qt bug.

[fmoc]

Needs to be tested on Wayland.

[saw-jan]

Tested with ownCloud 6.0.0.13177-daily20240122 [ab204c]

Confirmation dialog is always on top of new account setup window