After for the next time losing my mouse pointer when i tried to export json file. I tried to get to the cancel button to close the file dialog. So i can close interface.
Tab seems not to work in the file dialog. If you try to tab when in edit mode to export the json file you start to tab inside the edit.js window. Instead of jumping to the save or cancel button.
As solution for cancel or esc would be to make the ESC key working on QT windows. That gives you at least soem Escape when the mouse pointer is gone. Until the problem with disappearing mouse pointers is fixt.