The title says it all :)

Can I run a contest in a group at the same time an official contest (e.g., a usual CF round) is running?

Thanks!

A friend of mine used their Gmail to login. Seems like their handle name has become the same as their gmail address, but without "@gmail.com". - Is what I'm correct? - Is there any way for changing their handle name?

Thanks in advance.

Whenever I open any problem, whether from the problemset or contests page, whether on English or Russian version of the website, the website reopens the last page I opened, and a popup message says "Can't read or parse problem descriptor".

I've already known several people are having the same issue (don't know anyone not having it currently)

So, is there any announcement on this problem somewhere? And when is it expected to be fixed?

UPD: Problem is now solved, I think. I can open problems again :)