Webrender: Incorrect clipping on https://godotengine.org/download/linux

[nical]

Go to https://godotengine.org/download/linux using firefox nightly with WebRender enabled, and scroll around. Notice the clipping of the blue mascot on the left.

[gmorenz]

I can reliably trigger a firefox nightly crash on this page, I suspect the cause may be the same. For whatever reason the first crash report didn't get a stack trace.

Reproduction instructions: Load page, wave mouse around in bottom right corner (also sometimes elsewhere, bottom right corner is just really reliable).

1. Crash
2. Crash
3. Crash
4. Crash

Edit: Image of my window, since it seems likely it's the elements I wave the mouse over that matters not the absolute coordinates

[Darkspirit]

Offtopic: @gmorenz, I can confirm that your crash was fixed by #2490.

[Darkspirit]

WR @ 3d541ccee469638603ec194da09227c991642c64
mozregression --repo try --launch 3b33947edef50c7f1cf9ee1d5f087067df57863e --pref gfx.webrender.all:true startup.homepage_welcome_url:"https://godotengine.org/download/linux"
bad

WR @ 7ca4558f247ac02b9a49c0a9bf5d3972c451092f
mozregression --repo try --launch e9dc076b65fb82417dfe244c2516913c18f672b0 --pref gfx.webrender.all:true startup.homepage_welcome_url:"https://godotengine.org/download/linux"
good

Fix range: https://github.com/servo/webrender/compare/3d541ccee469638603ec194da09227c991642c64...7ca4558f247ac02b9a49c0a9bf5d3972c451092f

In the past I assumed that this could be a duplicate of #2334 (which I never mentioned, lol, sorry), which then itself has been marked as duplicate of #2584 (on Bugzilla).

Fixed by #2588. Thank you!

[glennw]

Assuming this can be closed, based on comment above. Please re-open if further work needed here.