Magic DNS, firefox doesn't recognize ssl cert on Synology DS?

First of all: Great piece of Software tailscale that is. I love it! Thank you so much!

But right now I’m heading a problem I wasn’t able to solve myself yet:
The topic almost says it all… I wanted to make use of the magic DNS feature and followed the instructions on the knowledge database for magic dns usage:
I logged into my Synology Diskstation via ssh and did “sudo tailscale cert” what was confirmed with "For domain, use “”.

when i try to log on the user interface via (the port set for DSM interface) in my firefox browser resolves the domain name correctly, but it won’t recognize the ssl cert and says the domain is insecure…
when I acknowledge that it let’s me pass on to the login interface, but not ssl secured…

Any suggestions what i could have done wrong?


—> Post can be deleted… was to dump to actually add desired domain that should get a certifcate in the command line, so nothing really happend.
After adding the device.ts-domain private pem and crt were generated and could be implemented by hand in DSM…now it works