1853075 - Scrolling up only works every other attempt on some pages (i.e. Google, Github, about:config)

Status: NEW

(Fenix :: Browser Engine, defect)

Description

[Andrew Gunnerson]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/117.0

Steps to reproduce:

1. Navigate to one of the affected sites. For example: https://google.com/search?q=firefox or https://github.com/mozilla-mobile.
2. Scroll to the bottom.
3. Attempt to scroll up.

Actual results:

Scrolling up only works every other attempt.

Screen recordings:

• Google: https://www.youtube.com/watch?v=gN31-r97YLM
• Github: https://www.youtube.com/watch?v=Sh38Trx-cpw

Expected results:

Scrolling up should work every attempt.

Comment 1

[Andrew Gunnerson]

I've tested this in 117.1.0 and nightly (119.0a1, Build #2015973955, 418fb80f34) and they both exhibit the same behavior.

From a user perspective, the symptoms seem similar to https://bugzilla.mozilla.org/show_bug.cgi?id=1724755, but I don't know if it's the same root cause, so I filed a new bug report (and the linked bug report is for a specific site anyway).

Comment 2

[Andrew Gunnerson]

I just noticed this happens with the builtin about:config page too.

Comment 3

[Mira Lobontiu (Android QA)]

I was able to reproduce this behavior only on about:config page on the latest Nightly 119.0a1 from 9/18 with Google Pixel 6 (Android 14), and HTC 10 (Android 8).

Not able to reproduce on the pages mentioned in the initial description.

Comment 4

[Mira Lobontiu (Android QA)]

Attachment: logcat.txt

Comment 5

[Andrew Gunnerson]

This seems to be fixed by https://bugzilla.mozilla.org/show_bug.cgi?id=1847305. None of the pages where I encountered this before exhibit the issue anymore after those commits were introduced.

Comment 6

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Fenix::Browser Engine' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.