Web IDE errors

Currently I use Gitlab 12.0.3

First of all, as can be seen from the attached file (the two arrows), the image assigned for the project is provided in the src attribute<img src='...'> with full URL and not relative. Which causes the https warning.

Second, the footer part 5e2788df by Jack Vox Jack Vox 4 hours ago... I have an assigned profile picture that is visible everywhere, but here.

Third, the message An error occurred whilst loading all the files.

Why the Web IDE won't load anything. And where might be the problem? My Gitlab is installed in container (Ubuntu18.04) and I use proxy pass with nginx to forward the traffic to this container.