Cannot login to web UI when using hostname in URL, only when using IP. Bug?

[jensb]

Hello,

I am using AGH on a Raspberry Pi which in our LAN is locally known as "raspberry64.fritz.box".
After the last upgrade to v0.107.53, when I go to http://raspberry64.fritz.box:3001, I do get the AGH login page, and entering the correct credentials prints "auth: user "admin" successfully logged in from ip xxx.xxx.xxx.xx" in the log, but I get redirected to the login page again. There is no error message. (There is a red error box however if I enter a wrong password.)

If I use http://IP-Adress:3001 and login the same way, I get successfully redirected to the main AGH dashboard.

Is this a bug or can it be a configuration issue?
I can resolve "raspberry64.fritz.box" successfully on the Raspberry box, using the 'host' command gets me both the local IPv4 as well as the IPv6 address.

Any help would be appreciated!