It looks like Katy Perry's not letting her feud with Taylor Swift die!

The singer may have allowed herself to be in the same room with her enemy at Drake's 30th bday bash on Sunday -- but that doesn't mean that the "Roar" singer isn't still taking every opportunity she can to throw some shade at her ex friend.

During Kanye West's concert in Los Angeles on Tuesday night, KP filmed herself dancing to Yeezy's "Famous," which infamously has headline-making lyrics about T-Swizz. Looks like "Fireworks" singer wanted to celebrate her 32nd birthday with some serious lady shade!

In the video, Katy pulls some faces, opens her eyes wide and then gets close to the camera -- just as Kanye raps, "I feel like me and Taylor might still have sex, why? I made that bitch famous!"

Eeek! Maybe you should let sleeping dogs lie?!