Bug 216107 - Negative values in cubic-bezier transform transitions do not work
Summary: Negative values in cubic-bezier transform transitions do not work
Status: RESOLVED DUPLICATE of bug 215826
Alias: None
Product: WebKit
Classification: Unclassified
Component: Animations (show other bugs)
Version: Safari Technology Preview
Hardware: All All
: P2 Normal
Assignee: Nobody
URL:
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2020-09-02 16:10 PDT by Joseph Pearson
Modified: 2020-09-03 02:18 PDT (History)
4 users (show)

See Also:

Attachments
Save as HTML and open in latest Webkit! "Animate: transform" is broken behavior; "Animate: top" is expected behavior. (1.73 KB, text/html)
2020-09-02 16:10 PDT, Joseph Pearson 		no flags Details
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Description Joseph Pearson 2020-09-02 16:10:35 PDT 
Created attachment 407829 [details]
Save as HTML and open in latest Webkit! "Animate: transform" is broken behavior; "Animate: top" is expected behavior.

When a CSS cubic-bezier easing function contains a negative value, and the transition property is `transform`, the property doesn't animate while in the negative range. It starts animating when the easing function enters the positive range.

**See attachment** for bug reduction with `transform` and expected behavior with `top`. The expected behavior with `transform` is observed in iOS 13, Chrome, and Firefox.

This bug was introduced between Safari 13 and 14. We have been using this animation feature at https://libbyapp.com for several years, and noticed it broke in Saf 14 betas.
Comment 1 Radar WebKit Bug Importer 2020-09-02 18:17:04 PDT 
<rdar://problem/68245777>
Comment 2 Antoine Quint 2020-09-03 02:18:36 PDT 
Thanks for filing this! This is a duplicate of bug 215826 which was fixed in r266280 last week.

*** This bug has been marked as a duplicate of bug 215826 ***