I wonder how the timeout happen in api/src/Mail/Credentials.php in a WebDAV PROPFIND request.
That is really strange …
Problem with PHP Fatal: Maximum execution time exceeded is, that you can’t get a trace from it (like an exception), but setting a higher max_execution_time (`EGW_MAX_EXECUTION_TIME environment variable in your docker-compose.override.yml) should give you more time, which either leads to the PROPFIND to succeed, or fail again with no further clue 
I looked yesterday into a similar case with WebDAV, exceeding a 30 second timeout, with just 170 folders in a collection. The strange thing is: the time spend in the VFS backend function for the directory listing is a fraction of a second.
I wonder if that’s a recent PHP problem somehow.
A user on the German forum had a wired LDAP problem, which turned out to be related to the PHP version of the package and which is supposedly fixed in the las PHP release, so you could give updating PHP a try:
docker exec -it egroupware bash
apt-get update && apt-get upgrade -y
exit
docker restart egroupware
Let me know if that helped.
Ralf
