Mayank Bansal, can you check if the problem happens with pref "gfx.webrender.dcomp-video-vp-scaling-win = false"?
Bug 1767185 Comment 9 Edit History
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Mayank Bansal, can you check if the problem happens with pref "gfx.webrender.dcomp-video-vp-scaling-win = false"? I wonder if the problem is related to video scaling.