Onyx Fixture Finder was an homemade tool, dev by myself 
I can understand your frustration, but it was planned to be removed initially more than 2 years ago. So it get already some extra life. (I was still also using it (this is why I dev it initially) )
Several reasons were requiring its closure, like confusing onyx user when not founding a given profile in the current library (no more accurate because no more up-to-date, example of trouble), high cost of hosting, maintenance still needed to avoid failures (hacking).