I'm trying to move a conversation to chat on a site I moderate. When I click the big button from the flag dialog, I get this:

It links to a chatroom that is most definitely empty.

I have also tried selecting the Mod > Move comments to chat button. This just reloads the page without deleting/moving any comments or posting the link to the chatroom.

I didn't post any links to the chatroom or post in question since I didn't want to attract too much attention to a random post. If an employee needs these links in order to hunt the bug down, I'd be happy to provide them.