I have exactly this issue too which I posted here
It does seem to happen sporadically. I notice that it only seems to be with the first open workflow. If there is only one open workflow and this behaviour occurs, opening another workflow brings the screen back to normal - but only for the second workflow. Return to the first one and it jumps back to the weird shift.
My only workaround for now is to have a dummy workflow open as the first tab and everything else is opened after this one… 