Thank's for reporting it! You are at least the third person to report that I think. I'm a bit unsure about it, I was unable to get that popup, even with a pretty outdated chrome version without ad-blocker and similar. Some websites say that it's a local infection, some say it's the site compromised, so I suggest scanning your system with a malware removal software, just to be on the sure side.

I'll poke the guy who has admin rights to the server to check for infections.

I'll give my Windows an infection scan, probably a good idea. I try to give it as few chances as possible to waste my time so I really only use it for gaming, but occasionally I do browse the web a little with it.

It was server side, it turned out. It should be fixed now, thanks to robn.

Ignore, apparently to get rid of saved drafts now you MUST post them?