Text field cannot be edited

When positioning a text it may occur that the little window you use to edit the texts properties will be partly hidden by the icons in the left upper corner (marker, text, etc), preventing the text from being edited

I have a similar problem. My text box is way off the bottom of the screen. What I do then is to take the mouse to a position on the map and pull it down. Sometimes I then get to the text box to move or edit.
However I do not dare to move (reposition) it because after the move, I get the following error on saving:-