To clarify, by "not working", I mean there is no clickable link associated with any function/variable etc.

I'm having trouble reproducing the issue. Please provide an example link.

Also, please note that there is a delay in computing Xrefs (we are working on how to speed it up) and this may cause Xrefs to be a little off or missing for new files. However, they should not be missing entirely for files that usually have Xrefs. 

Cross-ref is working now, perhaps it's an intermittent issue only.
Thanks for looking into this.

By the way, the problem didn't just occur to new files. There was no xref for files that had refs before.

OK. In case we can see anything in our logs, do you remember any file path you looked at?