I've attempted repro on a highend machine (Ryzen 7950X3D + Radeon RX 9070 XT, with two 3840x2160@240hz HDR monitors) using the links in comment #1, the numbers for Texture uploading time [ms] I see are as follows... * Firefox Nightly 139.0a1 (2025-04-15) (64-bit) * Regular image - number seems accurate on first time, after that it goes to 4ms and 3ms respectively but the observable jank looks just as long so measurement is inaccurate, only showing the first time numbers here, reloading the page still shows 4ms and 3ms (but again same long jank), closing the tab and reopening it after a bit seems to show the full time again for the first upload, then back to 4ms and 3ms * 8192x4096 JPG 142 first time * 204x2048 PNG 37 first time * ImageBitmap - these seem accurate so I'm including the full timing report * 8192x4096 JPG 4.4MB 44.00 / 50.00 / 47.32 / 66 * 2048x2048 PNG 4.5MB 5.00 / 7.00 / 6.58 / 65 * Chrome Version 135.0.7049.96 (Official Build) (64-bit) * Regular image * 8192x4096 JPG 4.4MB 135.00 / 142.70 / 137.91 / 13 * 2048x2048 PNG 4.5MB 38.90 / 41.20 / 40.12 / 12 * ImageBitmap * 8192x4096 JPG 4.4MB 44.70 / 52.30 / 46.15 / 13 * 2048x2048 PNG 4.5MB 4.60 / 5.00 / 4.82 / 12 * Edge Version 135.0.3179.85 (Official build) (64-bit) * Regular image * 8192x4096 JPG 4.4MB 129.70 / 147.90 / 133.54 / 13 * 2048x2048 PNG 4.5MB 38.30 / 41.20 / 40.01 / 12 * ImageBitmap * 8192x4096 JPG 4.4MB 44.10 / 46.90 / 45.02 / 13 * 2048x2048 PNG 4.5MB 4.80 / 5.20 / 4.96 / 12 Obviously at 240hz, anything over 4.1667ms guarantees jank, 142ms observed in Firefox is highly visible jank.
Bug 1486454 Comment 20 Edit History
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I've attempted repro on a highend machine (Ryzen 7950X3D + Radeon RX 9070 XT, with two 3840x2160@240hz HDR monitors) using the links in comment #1, the numbers for Texture uploading time [ms] I see are as follows... * Firefox Nightly 139.0a1 (2025-04-15) (64-bit) * Regular image - number seems accurate on first time, after that it goes to 4ms and 3ms respectively but the observable jank looks to be at least as long as the ImageBitmap case, only showing the first time numbers here, reloading the page still shows 4ms and 3ms (but again jank), closing the tab and reopening it after a bit seems to show the full time again for the first upload, then back to 4ms and 3ms reported but visible jank * 8192x4096 JPG 142 first time * 204x2048 PNG 37 first time * ImageBitmap - these seem accurate so I'm including the full timing report * 8192x4096 JPG 4.4MB 44.00 / 50.00 / 47.32 / 66 * 2048x2048 PNG 4.5MB 5.00 / 7.00 / 6.58 / 65 * Chrome Version 135.0.7049.96 (Official Build) (64-bit) * Regular image * 8192x4096 JPG 4.4MB 135.00 / 142.70 / 137.91 / 13 * 2048x2048 PNG 4.5MB 38.90 / 41.20 / 40.12 / 12 * ImageBitmap * 8192x4096 JPG 4.4MB 44.70 / 52.30 / 46.15 / 13 * 2048x2048 PNG 4.5MB 4.60 / 5.00 / 4.82 / 12 * Edge Version 135.0.3179.85 (Official build) (64-bit) * Regular image * 8192x4096 JPG 4.4MB 129.70 / 147.90 / 133.54 / 13 * 2048x2048 PNG 4.5MB 38.30 / 41.20 / 40.01 / 12 * ImageBitmap * 8192x4096 JPG 4.4MB 44.10 / 46.90 / 45.02 / 13 * 2048x2048 PNG 4.5MB 4.80 / 5.20 / 4.96 / 12 Obviously at 240hz, anything over 4.1667ms guarantees jank, 142ms observed in Firefox is highly visible jank.