boulderLinks work, but broken links do not appear as broken so they're a little confusing. I've had a lot of people tell me links are broken, but everyone is just clicking the same stupid links in the S21 thread that don't work in the first place. There's no target specified on them.
The threads view is sometimes a little broken when doing pulldown refreshes, or getting the next page of elements. I haven't fully investigated that issue, but it works if you change between the sorting a couple times.
No, it appears that *links*, using the URL bbcode, are broken. If it's a plain text URL then it works fine. I tested this on the link I posted above, where I had text that wasn't the URL itself. I then tested it on an actual URL that someone just pasted that auto-linked, and that works fine.