Created attachment 114501 [details] demonstration Watch the screencast recorded on Arch Linux please.
This is probably https://bugreports.qt.io/browse/QTBUG-18308
Yep, that's it. I encountered this during the initial port and was tearing my hair out trying to figure out the issue. Nice to know it was a Qt bug and not me. :) Shame those really long pt-br strings trigger the bug, though.