PUML previews are always cut off at bottom

[mmoser18]

The right-hand side preview pane of the ASCII-Editor which shows the generated GraphViz/PUML output is always cut off at the bottom. Typically one can only see the upper 1/2 of a picture and - for wide pictures - sometimes even only the top 1/10 or 1/20 or so of the actual picture - I hope the attached screenshot makes the issue clear.

One also can not scroll or pan around on that picture making that preview almost useless (one can essentially only use it to right-click on the picture-fragment and select "Save as picture file" to save the entire picture to a file that one can then inspect with a different viewer). The corresponding IntelliJ plugin handles this MUCH better - there the preview is actually helpful!