How do remove connection with 3rd party site?

[Heron]

Hi, how can I remove any connection with 3rd party site like challengeme.gg or others? On the challengeme site I see the information that I canno 'unlink' steam from this site. It's very annoyoing. Please help.

[Zekiran]

Well that's a risk that you take, putting your credentials on shady 3rd party sites, isn't it. You probably cannot, that's how they get accounts phished...

[MrUnclean]

you probably cant do it so if it is security you are worried about you could add steam guard to be sure

[Kargor]

There's only one legitmate link, and it doesn't require removal. It's up to whatever site you're looking at to decide whether they let you remove or change it.

When using "Login through Steam", the other site receives no useful information whatsoever. They basically get a link to your profile page, and a confirmation from Steam telling them that whoever is doing the clicking on the browser right now knows how to log into that Steam account.

Steam doesn't do anything else. Websites usually call this "linking your Steam account", but this goes one way one -- they store the link they got. Steam, on the other hand, doesn't care at all.