Yotube oEmbed broken

[dantefromhell]

I'm using Wiki 2.0.3 on HumHub 1.14.5

In a wiki page I have embeded a youtube video, which triggers the confirmation dialog for external content.

After clicking Confirm without the selecting 'Always allow content from this provider' the question text gets displayed again, without the button and some missing stylesheets, instead of the video frame.

Viewing the wiki page from the stream space works as expected, after confirming I am able to watch the YT video.