Hi, I use firefox nightly as my everyday driver for WEB. So far I was very satisfied with the performance and mostly with youtube videos and hardware decoding. I use a Nvidia 1060 (GP106) which supports VP09/AVC1/H265 decoding. The problem started only recently after some updates of the Firefox when I noticed that VP09 isn't hardware accelerated anymore. They way I test is using the Windows 11 task manager/Performance/GPU/Video decode. At the same time, the stable Firefox has no issues with VP09 HW decoding. The same is valid for any other browser I tested. So the problem is isolated to the nightly. I downloaded and ran mozregression GUI which indeed showed me that some nightly version before the VP09 worked just fine. I tested using the dates option of the tool. This is [https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=4e611bdae88f779250feae9326aa3c2af80c88e9&tochange=2408bee8bcc4ba4eb54c92662a4a2b55dd22b210 the push_log URL] from my test. Thanks in advance for your help