Another "login" problem

So it used to be magical before; I click “sign in with steam”, I type in my login and password, and it works out.
Now whenever I just click “sign in with steam”, I instantly get

Content Encoding Error (content_encoding_error)

Server response could not be decoded using encoding type returned by server.
This is typically caused by a Web Site presenting a content encoding header of one type, and then encoding the data differently. 

Plus that’s not only in the steam sign in link(, that also happens in So I’m limited to only use Toybox, which isn’t that “Woo awesome” since I’m trying to get some tools, playermodels…etc.
I tried using IE 8 instead of Firefox (3.8/5 not beta) but that didn’t work out, so is it some maintenance in the website or am I experience an unusual problem?
Much appreciated.