Problem with firefox and own domains

Hi, I tried to register with 2 of my own domains what are used all over the Internet  for e-mail etc and never had a problem.
Here both were flagged as false.
OK I use only 1 letter and then the 4 letter domain, but that should not cause a problem.
I finally had to resort to Opera and protonmail to be able to register, but still login does not work with with newest version of firefox.
I am also searching the over 18 section with all the fun promised, any hint?
thank you
Sandas

You can only log into the over 18 section if you are under 25 sorry and that rules you out. First mistake I have to say .

Hi Sandas. Sorry you're having problems. I am using Firefox Quantum 66.0.4 which is the latest version as we speak and have no problems. I am going to reduce the size of your avatar as it exceeds the limits allowed and is rather long. I suggest you just keep using whichever browser allows you to connect as you have managed to log in somehow.