Hey everyone,
Thanks for all your responses. The error is not shown anymore, and I can also not reproduce it (maybe just temporary problem?).
@PriyaVR: My browser language was set to "English (United States)", I did not try to change it yesterday while the error occurred. Today even if I change it to German, I cannot reproduce it.
@ragavanrajan I tried hard refresh and restart the browser yesterday, but it didn't solve the issue.
@OliverRodrigues It tried the "Default design template". In the beginning the icons were shown (I was taking Screenshots for a blog post), but then stopped. Also creating another site didn't help.
Therefore the issue seems to be solved, I will close this topic. If anyone else experience this, please leave a comment and maybe what you tried, if it also resolves the issue, I will mark it as solution.
Thanks everyone!
Best regards
Marvin
Blog: Cloudkumpel