sorry for the late answer, didn't notice that someone replied already D:

I'm using firefox (always the newest version, i think it's 49.0.2 atm) on a windows 7 64bit.
Sometimes it happens right after visiting the starting page et.trackbase.net, but sometimes it also happens after i open the link to a server page and sometimes it doesn't happen at all.
Usually the first thing I do is logging in, so i don't know if it would also happen when i'm not logged in.
In the network tab i can't see anything weird right now (but atm the site is working fine), i'll try to keep an eye on it the next times when i visit the page.
What do you mean by 'console tab'? cmd.exe or something else? Not too familiar with this kind of stuff

Greetings,