Creating a simple CSS animation fires random rafs every 2-20ms. In some of these rafs animated element is not moving. See console for the following snippet: <style>button { transition: margin 500ms linear 0s; margin-left: 0; }</style> <button id=button>Hello</button> <script> requestAnimationFrame(foo); let lastFrame = performance.now(); function foo(time) { console.log(time - lastFrame); lastFrame = time; console.log(button.getBoundingClientRect().x); if (button.getBoundingClientRect().x < 100) requestAnimationFrame(foo); } setTimeout(() => { button.style.marginLeft = "100px"; }); </script>
Created attachment 398686 [details] Patch
Created attachment 398690 [details] Patch
Comment on attachment 398690 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=398690&action=review r=me > Source/WTF/wtf/PlatformUse.h:190 > #define USE_REQUEST_ANIMATION_FRAME_DISPLAY_MONITOR 1 There going to be a followup that removes references to this USE statement?
Comment on attachment 398690 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=398690&action=review >> Source/WTF/wtf/PlatformUse.h:190 >> #define USE_REQUEST_ANIMATION_FRAME_DISPLAY_MONITOR 1 > > There going to be a followup that removes references to this USE statement? Yup.
Comment on attachment 398690 [details] Patch Clearing flags on attachment: 398690 Committed r261264: <https://trac.webkit.org/changeset/261264>
All reviewed patches have been landed. Closing bug.
<rdar://problem/62959022>