What steps will reproduce the problem?
I'm using YouTrack 2018.3 Build 48045 behind a reverse Proxy (IIS; Request to 'youtrack.mydomain.com' gets resolved to 'localhost:8080', where youtrack service runs on port 8080).
The Base-URL is set to 'youtrack.mydomain.com' and everything is working fine! But after some time (don't know what triggers it and don't know how to reproduce it!) the Base-URL is changed (automatically?!) to 'youtrack.mydomain.com:8080' resulting in wrong links on Tickets on the dashboard (using Issue List 1.0.3). I've noticed the following changes on the audit page:
...
2019-01-13 04:04:32.743 Update Service: YouTrack Service: YouTrack
2019-01-13 04:04:30.196 Update Service: YouTrack Administration Service: YouTrack
2019-01-13 04:03:26.985 Remove Service: Temporary installer service (2019-01-13 04:03:26 MEZ) Service: Temporary installer service (2019-01-13 04:03:26 MEZ)
2019-01-13 04:03:26.578 Create Service: Temporary installer service (2019-01-13 04:03:26 MEZ) User: guest
...
Nobody is using the youtrack at that time. And the two 'Update' events changed the Base-URL from 'youtrack.mydomain.com' to 'youtrack.mydomain.com:8080'! Do the 'Temporary installer service' have to do something with the change? And how is the guest user creating an 'installer service'?
When I change the Base-URL back, everything is working fine again, but after some days the Base-URL is going to change again automatically!