The background I bought from the auction house, the Extractor I made in Crafting.

Any ideas?

Hi,

You can assign a background directly on the pet's profile page similar to other types of apparels. Open a pet profile page, select "Wardrobe" tab and switch the selector at the top of this tab from "Apparels" to "BGs". All available backgrounds will be there.

The Deviance Extractor works only during events that allow the use of Liquid Deviance, namely during the annual Tundra event. It has ended in the beginning of March so right now it's not possible to use the Deviance Extractor.

My bad about the Extractor, thanks for clearing that up.

However, the background is bugged. It shows up in my inventory under apparel, but not in the pet's list of backgrounds. (see pic attached)

By now I made several custom backgrounds from the tack workshop, and I found another background with the same problem. it's called "Sunset Background"

Sorry for the delayed reply! The situation in Ukraine is still far from calm, so, unfortunately, I was able to look further into your report only today.

This background was restricted to Gryphons. However, judging by its description, the artist wanted it to be availbale for all species, so I removed the restriction. You may now use it with any pet. 

Thank you so much! 

I didn't know you live in the Ukraine. You guys are heros! I hope everything can go back to normal for you soon in the future! <3

Thank you so much for your kind words :) We too hope this madness ends soon and we can get back to peaceful life and fruitful work!