1682770 - Logviewer adds/removes scrollbar at certain window sizes causing constant jiggle

Status: NEW

(Tree Management :: Treeherder, defect)

Description

[Jan-Erik Rediger [:janerik]]

Attachment: logviewer-jiggle.mp4

Probably best described with a video, which I'll attach.

When my Firefox window is taking the screen width the logviewer jiggles between displaying a scrollbar and hiding it.

>> window.screen
Screen { availWidth: 2560, availHeight: 1417, width: 2560, height: 1440, colorDepth: 24, pixelDepth: 24, top: 0, left: 0, availTop: 23, availLeft: 0 }

When changing the window width just slightly (couple of pixels) it stops that. I assume that for some CSS query that size is the exact edge case and adding the scrollbar pushes it below the limit again, which triggers removing it, which pushes it above the limit, which ... you get the idea.

I had that a long while ago already, but then it was definitely not occuring for the past months, but started reappearing now for a couple of days or weeks.

Tested on this log: https://treeherder.mozilla.org/logviewer?job_id=324147123&repo=try&lineNumber=1534

Firefox Nightly 86.0a1, 20201215092954, macOS

Comment 1

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

Does this bug fit in here or does it belong into react-lazylog?

Comment 2

[Hassan Ali (:hassan)]

Here's the same log but in firefoxci: https://firefox-ci-tc.services.mozilla.com/tasks/KZmXKY_uR86Zx7YBJx2A5A/runs/0/logs/https%3A%2F%2Ffirefox-ci-tc.services.mozilla.com%2Fapi%2Fqueue%2Fv1%2Ftask%2FKZmXKY_uR86Zx7YBJx2A5A%2Fruns%2F0%2Fartifacts%2Fpublic%252Flogs%252Flive_backing.log

If you are able to see the same bug then I would say it's a react-lazylog issue. Otherwise, it's probably a regression from the Treeherder side.

Comment 3

[Jan-Erik Rediger [:janerik]]

No jiggle on that link for me.