Branching Database building screen too small

Hi everyone

Latest update Win 10

Chrome, Edge & Firefox - all the lastest versions

Moodle - latest version and a new installation of h5p about two weeks ago.

I would like to make a branching database  - but - I can't get it to display properly. There is no arrow to load it full screen size like there usually is.

See: https://drive.google.com/file/d/1TAXf1c_DkMferh4NlcCmMAy4jwJFHTC7/view?usp=sharing or the attached image.

Does anyone have any idea please :-)

Thanks

Carol