When closing some dialog/widget by clicking OK/Cancel button and reopening the dialog/widget, everything works just fine. However, once clicking Windows [x] to close, reopen
the dialog/widget, all widgets are not visible any more but resizing will show again.

Attaching a sample and when you click on 'open log' button and close the log dialog with [x] button and reopen it, it is shown as empty.

Issue only in 5.12.4, it is working fine with 5.12.3 and 5.13.0