A420 is YUV+alpha in a separate component. vp9dec outputs this format for assets encoded with alpha support. Our sink could support this format and let the TextureMapper handle the final conversion to RGBA.
Created attachment 433503 [details]
Comment on attachment 433503 [details]
lgtm but it might be interesting if somebody with more graphics knowledge can have a second look
Committed r279938 (239682@main): <https://commits.webkit.org/239682@main>
All reviewed patches have been landed. Closing bug and clearing flags on attachment 433503 [details].