I performed the disabling of all extensions but the problem remained. Your hint about the lazy loading put me on the right track though. In our “The Gem” WordPress theme I found the parameter where it is set and I changed it from JS Lazy Loading to Native Lazy Loading and it solved the issue.
So, as you said earlier, we can now close this issue.
This reply was modified 2 weeks, 3 days ago by uberdude.