How to access Syncthing Web GUI via FQDN?

Good evening everyone,

I have weird problem: I have installed Syncthing (charts) on TrueNAS SCALE, and I can only login and access Syncthing Web GUI via IPv4 address of my TrueNAS instance. (I have set-up username and password for Syncthing Web GUI protection, and I don’t use HTTPS) and via IPv4 address is everything ok.

But I would like to access Syncthing Web GUI via FQDN of my TrueNAS (the name it has assigned from DNS on my local network).

Unfortunately I can only access login page, but whenever I provide credentials (it doesn’t throw any error, like wrong username or password), but it just drops back to login page again, and doesn’t go through to Web GUI of Syncthing.

I’m using:

Syncthing (charts):
App Version: 1.27.4
Chart Version: 2.0.3

Thank you in advance for some help, have great evening everyone.

Update: actually, it seems like the problem is related to Safari browser only, Chrome is working well. Looks like I will have to investigate whats going wrong in Safari instead. :frowning: