1418256 - Layout is shaking

Status: NEW

(Core :: Layout, defect, P3)

Description

[legezam]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:57.0) Gecko/20100101 Firefox/57.0
Build ID: 20171112125346

Steps to reproduce:

1. open facebook wall
2. start scrolling down
3. there are certain scroll states where you have to stop and observe what you see on the screen
(this is extremely hard to reproduce)


Actual results:

If you stop scrolling, you see some layout elements shaking vertically. It looks like ffx cannot decide the final height of the elements and always recomputing different values. (this is a hard quess)
OSX Sierra, Macbook Pro late 2013.
I have a screen recording about it, but as it contains sensitive information (my facebook wall), i wouldn't like to share it publicly. I can send it privately to mozilla if needed.


Expected results:

The layout is computed, rendered and remains in a final and stable state.

Comment 1

[Andre Klapper]

Please provide exact screen width and browser zoom level information.

Comment 2

[legezam]

Screen size is retina scaled to 1680x1050. Zoom level is set to 100%. The browser window is filling the entire screen.

Comment 3

[Nicolas Silva [:nical]]

Attachment: Screencast

I think I just ran into this bug.

Comment 4

[Ted Campbell [:tcampbell]]

I get the same behaviour as Comment 3 on reddit. It happens both Win10 + Intel (no webrender), and Win10 + Nvidia (default on webrender). Both cases are 150% OS DPI scaling and 100% browser zoom.

When this happens, the CPU hits 100% as refreshdriver keeps firing. Often if I scroll up the shaking/CPU stops and when I scroll back (keyboard up/down arrows) the shaking starts again. I don't have more specific STR.