1759919 - document.getWireframe doesn't return significant rects for cbc.ca

Status: VERIFIED FIXED

(Core :: Layout, enhancement)

Description

[Mike Conley (:mconley) (:⚙️)]

STR:

1. Open the Browser Toolbox
2. Visit https://www.cbc.ca
3. After the page finishes loading, switch to the Console tab
4. At the right-most end of the Console input, click on the item that says "Top" to show a list of processes / contexts we can switch to. Switch to the cbc.ca one in the second block, the one that shows the PID at the start.
5. In the console, type:

tabs[0].content.document.getWireframe(true);

ER:

The returned wireframe should contain rects for the main elements of the page, including the "main story" on the site.

AR:

The returned rects appear to be for the header and the scrollbar, but nothing else.

Comment 1

[Mike Conley (:mconley) (:⚙️)]

Interestingly, if you repeat steps 1-4 of the STR, and then type in:

tabs[0].content.windowUtils.nodesFromRect(0, 0, 0, tabs[0].content.innerWidth, tabs[0].content.innerHeight, 0, true, false, true)

you get the same restricted number of nodes. If however, you then type in:

tabs[0].content.windowUtils.nodesFromRect(0, 0, 0, tabs[0].content.innerWidth, tabs[0].content.innerHeight, 0, true, false, false)

then we get far more nodes - apparently, the aOnlyVisible argument is restricting us somehow here.

Any idea what's going on here, emilio?

Comment 2

[Emilio Cobos Álvarez [:emilio]]

Attachment: Bug 1759919 - Improve getWireframe() handling of canvas background. r=mconley

Don't include it twice, and compute it explicitly since PresShell's
GetCanvasBackground gets computed during painting otherwise.

Comment 3

[Emilio Cobos Álvarez [:emilio]]

Attachment: Bug 1759919 - Don't stop looking for intersecting frames too early in case there are fully-opaque transformed elements. r=miko!,mconley!

nsDisplayTransform::HitTest clips the rect it passes to its children,
and thus intersecting the whole area isn't relevant.

Depends on D141300

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/52120ef3072f
Improve getWireframe() handling of canvas background. r=mconley
https://hg.mozilla.org/integration/autoland/rev/84fa6be07a61
Don't stop looking for intersecting frames too early in case there are fully-opaque transformed elements. r=miko,mconley

Comment 5

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/52120ef3072f
https://hg.mozilla.org/mozilla-central/rev/84fa6be07a61

Comment 6

[Ardelean Oana, Desktop Test Engineering [:oardelean]]

Reproducible on a 2022-03-14 Nightly build on macOS 11. Verified as fixed on Nightly 102.0a1 (20220502213947) on macOS, Win10 64-bits, Ubuntu 20.04.