I don't know, but I'll check with people who might know.
Thanks.
CrystalMoon, thank you.
That problem is being addressed. Until it's resolved you can reach support via email at support@chess.com
Are you using chrome on windows or mac? Do you see any errors? Try to right-click on the page that fails and click on "Inspect Element" and then see if you can find any errors from the console!
http://i.imgur.com/q2CKpfj.png
erik, I tried both, Chrome on Mac and Chrome on Windows. There are no errors in HTML code of that page.
I solved the problem, on my system at least.
Pop-ups are blocked, with an exception for *.www.chess.com. The recent change uses a domain of support.chess.com which does not match the pop-up exception.
In Chrome this is via menu->settings, press the "show advanced settings" link, press the "content settings" button under the privacy section, press "manage exceptions" under pop-ups.
Edit: Another solution would be to not use a popup for an "are you sure" question. If I'm contacting support, usually I'm sure. Though I can see that this is helpful to cut the noise from the general population. 
Edit2: Include some code in the popup which complains if it is blocked. I know this is possible but would need to research to know how to do it.
If you need help, please contact our Help and Support team.
Dear support team,
This form doesn't work:
https://support.chess.com/customer/portal/emails/new
I'm using Chrome. When I click 'Send' button, nothing happens. I filled in all necessary fields and tried a zillion of captchas. No luck.
Regards, Sergiy