Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator at [no address given] to inform them of the time this error occurred, and the actions you performed just before this error.
More information about this error may be available in the server error log.
I can get to syncthing webui using the ipaddress and corresponding port or using a ssh tunnel but that's pretty much the same thing. I also didnt find anything relevant in /var/log/apache2/error.log