All users were logged out of Bugzilla on October 13th, 2018

Descendants of scrollable elements with 'perspective' get incorrect overflow areas when the scroll position changes

RESOLVED FIXED in Firefox 35

Status

()

RESOLVED FIXED
4 years ago
4 years ago

People

(Reporter: roc, Assigned: roc)

Tracking

Trunk
mozilla36
Points:
---

Firefox Tracking Flags

(firefox35 fixed, firefox36 fixed)

Details

Attachments

(1 attachment)

The transform on the child of a scrollable element with 'perspective' may be dependent on the scroll position. When the element is scrolled, the transform may need to be updated, but it isn't.
Created attachment 8519760 [details] [diff] [review]
Recompute overflow areas of transformeparent element with perspective is scrolled
Attachment #8519760 - Flags: review?(matt.woodrow)
Attachment #8519760 - Flags: review?(matt.woodrow) → review+
Actually there's an edge case not handled here: updating the overflow areas of the descendants could cause the overflow area of the scrolled frame to shrink, which we're not handling. And that could change the scroll position so I think there's actually a dependency loop in CSS :-(

But we probably should check this in anyway.
https://hg.mozilla.org/mozilla-central/rev/9906eabbfd3a
Status: NEW → RESOLVED
Last Resolved: 4 years ago
Resolution: --- → FIXED
Target Milestone: --- → mozilla36
Comment on attachment 8519760 [details] [diff] [review]
Recompute overflow areas of transformeparent element with perspective is scrolled

Approval Request Comment
[Feature/regressing bug #]: none
[User impact if declined]: incorrect rendering when scrolling in certain sites that use preserve-3d
[Describe test coverage new/current, TBPL]: some automated tests
[Risks and why]: I was contacted by a Web developer who's hitting this bug in the wild. The patch is very low risk so getting a fix out six weeks earlier would be good.
[String/UUID change made/needed]: none
Attachment #8519760 - Flags: approval-mozilla-aurora?
status-firefox35: --- → affected
status-firefox36: --- → fixed
Attachment #8519760 - Flags: approval-mozilla-aurora? → approval-mozilla-aurora+
I just landed the **reftest manifest changes only** from this bug on aurora and beta, because those changes actually belonged in either bug 1097437 or bug 1092842, which were just landed in both places:

https://hg.mozilla.org/releases/mozilla-aurora/rev/187e9fa68b67
https://hg.mozilla.org/releases/mozilla-beta/rev/c486cd17bebb
You need to log in before you can comment on or make changes to this bug.