1491707 - Scrolling gets stuck on some pages and divs

Status: UNCONFIRMED

(Core :: DOM: UI Events & Focus Handling, defect, P2)

Description

[Andrew Engelbrecht]

User Agent: Mozilla/5.0 (X11; Fedora; Linux x86_64; rv:62.0) Gecko/20100101 Firefox/62.0
Build ID: 20180904093908

Steps to reproduce:

Visit:  https://www.youtube.com/watch?v=8Y5cftds7-8&list=PLtKNX4SfKpzWo1oasZmNPOzZaQdHw3TIe&index=1

Pause the video, then move the pointer to the playlist on the right. Use two finger scrolling or scroll with a trackpoint by holding down the middle mouse button. Scroll half way down, then stop scrolling. try scrolling back up again. Then try scrolling down, then up, etc.

I'm using Fedora 28 GNU/Linux.


Actual results:

When trying to scroll back up again, the div only scrolls up a few millimeters or a few centimeters, then stops. Scrolling down again lets you scroll further, but sometimes that gets stuck as well.

I've seen this on other pages as well, but this is the only example I have right now.


Expected results:

Scrolling up and down in that div should not get stuck.

Comment 1

[Peter Magyari (Desktop QA)]

Hello Andrew,

Since I don't have access to Fedora on a device that has touch-scrolling capability I tried to reproduce this issue on Ubuntu using Firefox 62.0 / Firefox Beta 63.0b7 / Firefox Nightly 64.0a1 but I could not reproduce it.

Could you please test if the issue is reproducible in safe mode, here is a link that can help you do that:
https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode

If the issue still occurs please try it using a new profile, you can find the steps here: https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles?redirectlocale=en-US&redirectslug=Managing-profiles#w_starting-the-profile-manager

Thank you!

Comment 2

[Andrew Engelbrecht]

I tested safe mode and a new profile, but the issue remained. I also tested an Ubuntu 18.04 Live USB with an version of Firefox upgraded via apt-get, and the problem was there too, but less severe.

Some of the differences on Ubuntu compared to Fedora were that it got stuck less often, it scrolled faster and further, and it more frequently got stuck on the way up rather than the way down.

I also noticed that if I eased off on the track point, which would normally slow down the rate of scrolling if this weren't a bug, the scrolling would get unstuck at which point I could scroll faster until it got stuck again. Incidentally, this is also the case on Fedora, but the speed at which Firefox on Fedora gets stuck, and the slower speed to unstick the scrolling, were both much slower, by about an order of magnitude compared to Firefox on Ubuntu.

Comment 3

[Peter Magyari (Desktop QA)]

I'm unable to reproduce this issue on Ubuntu 18.04, and I don't have access to Fedora on a device with a track-pad, however I'm going to set a component that I think would be a good starting point in order to involve the development team in reviewing this issue.

Thank you.