Bug 285097 – [view-transitions] Wrong sizing when using CSS `zoom` property

• Status: RESOLVED
• Resolution: DUPLICATE
• Component: Layout and Rendering

[Onur Gumus]

Created attachment 473638 [details]
Page 1 title temporarily bleeding out

As title says I noticed some unusual behavior with cross document view transitions.
The demo is here:

https://glitch.com/edit/#!/rare-patch-fibula?path=index.html

There is a title Page 1 which needs to go smaller, but it bleeds out to lower portions of the page for some reason for few hundred milliseconds.

It works fine on chrome.

Screenshot attached.

[Karl Dubost]

It doesn't happen for me on macOS


```
Safari Technology Preview  209          20621.1.6
Firefox Nightly            135.0a1       13524.12.18
Google Chrome Canary       133.0.6914.0  6914.0
```

[Onur Gumus]

It DOES happen for me on macOS with Safari Tech Preview Release 210 (Safari 18.2, WebKit 20621.1.8.111.2)

[Onur Gumus]

Possible regression?

[Radar WebKit Bug Importer]

<rdar://problem/142172248>

[Tim Nguyen (:ntim)]

This isn't specific to cross document view transitions. I think we just ignore the CSS zoom property when taking snapshots for View Transitions.

If you replace `zoom: 0.5` with `transform: scale(0.5)`, it works fine.

Seems like an edge case that's a bad interaction with a very old feature.

[Tim Nguyen (:ntim)]

Created attachment 473756 [details]
Testcase reduction

Here's a test reduction.

[Onur Gumus]

Thanks for looking into this! Personally, I find the zoom property incredibly useful—often even more so than transform in certain cases—because it adjusts to the new layout, whereas transform does not.

I also came across a renewed specification for zoom:
https://chromestatus.com/feature/5198254868529152

It would be great to see this supported via view transitions.

[Matt Woodrow]

This should be fixed by 293466

*** This bug has been marked as a duplicate of bug 293466 ***