@esackbauer you are right. I have some customizations in my setup since I run mailcow behind a HTTP reverse proxy, but nothing I would relate to application performance what might slow down the rendering of the admin pages.
Which logs are interesting for this issue?
The container logs of php-fpm-mailcow do not show anything “bad” - see yourself:
Here is another excerpt for the logs - this time from nginx - showing roughly the same information:
After these lines in the container log I received a 504 error in the browser.
(Addresses in that log entries are almost all from the mailcow container network)
Where may I look for further clues?