Bug 194765 - Paused CSS animation with negative delay doesn't always compute the correct value on load
Summary: Paused CSS animation with negative delay doesn't always compute the correct v...
Status: NEW
Alias: None
Product: WebKit
Classification: Unclassified
Component: Animations (show other bugs)
Version: Safari 12
Hardware: All Unspecified
: P2 Major
Assignee: Nobody
URL: https://codepen.io/scottkellum/pen/28...
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2019-02-17 13:28 PST by Scott Kellum
Modified: 2019-02-18 11:32 PST (History)
8 users (show)

See Also:


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Description Scott Kellum 2019-02-17 13:28:08 PST
Rem units are intermittently miscalculated on load within animations. This happens in Safari 12 both on my Mac and iOS. Occasionally it will render correctly but on refreshes it more often than not renders incorrectly.

Replicate the bug:
https://codepen.io/scottkellum/pen/28d147aa4b21d84367ce832a986cd549?editors=1100


Possibly related: https://bugs.webkit.org/show_bug.cgi?id=194749


If the animation is toggled off and back on or set late with javascript it will work again.
Comment 1 Radar WebKit Bug Importer 2019-02-18 11:30:48 PST
<rdar://problem/48171742>
Comment 2 Simon Fraser (smfr) 2019-02-18 11:32:27 PST
Seems to only reproduce with Web Animations enabled.