The first video users open should be shown properly, at the moment if it is a video-the popup is really small.
Every image users open should be shown properly, at the moment 1st time you open each image you see only an empty popup and second time it shows you the image
Single choice set and Summary have the vertical scrollbar and there is a space to show all content
First video you open you see it like this:
Next time when you open the same video or some other content - popup resizes properly
Can be tested here: https://staging.h5p.org/node/302360