If I paste this failure into Findit, it says it's not pointing to a build.

https://luci-milo.appspot.com/p/chromium/builders/luci.chromium.ci/linux-xenial-rel/167

However the old format is still working (and if you follow the link you get redirected to the url above)
https://findit-for-me.appspot.com/waterfall/build-failure?url=https://luci-milo.appspot.com/buildbot/chromium.linux/linux-xenial-rel/167&debug=1

This prevents sheriffs from copying url to the failure and pasting into findit.