Bug 230106 – Safari Transitions No Longer Convert Between px and %

• Status: RESOLVED
• Resolution: DUPLICATE
• Component: Animations

[Matthew Pringle]

This is iOS 15 beta 8 Safari

This CSS code previously worked, where adding a class to start the transition would animate from 100% to 0px.

transition: top 0.25s;
top: 100%;
html.active {
    top: 0px;
}

The above has stopped working in iOS 15 Safari Beta 8, but the below works, replacing the px with %

transition: top 0.25s;
top: 100%;
html.active {
    top: 0%;
}

[Radar WebKit Bug Importer]

<rdar://problem/82932304>

[Antoine Quint]

Matthew, when you say "stopped working in iOS 15 Safari Beta 8", do you mean it worked in previous beta seeds of iOS 15, or just iOS 14? Thanks.

[Matthew Pringle]

Stopped working between iOS 14 and iOS 15 beta 8. It was not tested in any other betas.

[Matthew Pringle]

iOS 14.4 to be exact

[Antoine Quint]

Oh, I think this is a duplicate of bug 228811.

[Antoine Quint]

*** This bug has been marked as a duplicate of bug 228811 ***

[Matthew Pringle]

I will check tomorrow as my app also animates widths on some progress bars and so should fail on those aswell.

Tested in iOS back to 12.4 and it is fine in those versions.

[Matthew Pringle]

The other transitions work fine in iOS 15 beta 8 and so yes it seems to be a duplicate of https://bugs.webkit.org/show_bug.cgi?id=228811

Thanks for the help