When a QTabWidget has strong focus and is in the tabOrder list there is an infinite loop when you go to the next field with TAB

When a QTabWidget has strong focus and is in the tabOrder list there is an infinite loop when you go to the next field with TAB on QT 5.12.2

It doesen't work also on the preview of the form on Qt Designer. See attached form for an example. 

It does work propertly on Qt 5.8 and Qt 5.15.0

Can you give us a patch for the affected version ?

Qt 5.12.2 compiled from sources on Linux Centos 7 OS

Thanks,

Matteo, Sogea Srl, Italy

Edit:

Missing info:

The application is distribuited using Qt 5.12.2, I can't afford to upgrade the existing installations to 5.12.9

But I will try on the test server with that version and let you know the result.