If I pin a number of jobs and then try to cancel them via the dropdown on the pinboard, I get a 400 bad request error every time.
Huh, I didn't even know that was a thing you could do in treeherder. Are they taskcluster tasks? If you link me to them I can try to investigate a bit.
I have no clue where that code lives. Maybe Armen does?
Just pinned two taskcluster-based jobs on inbound and chose the "Cancel All" option from the pinboard dropdown and the requests succeeded, and I now see the jobs as canceled in Treeherder's UI.
Same results pinning two taskcluster jobs on beta. Tried the same canceling two buildbot jobs on beta and the network requests succeeded, but I haven't seen the canceled jobs appear in the UI yet.
Hrm, it's working here now too. Maybe stale TC credentials or something before. I'll reopen if I come up with STR in the future.