1516037 - on Win10, trackpad scroll gesture doesn't work in "Source" editor window on v2.overleaf.com

Status: NEW

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

Description

[sorcererofdm]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:63.0) Gecko/20100101 Firefox/63.0

Steps to reproduce:

Go to v2.overleaf.com and open a doc (for example https://www.overleaf.com/latex/templates/template-for-submissions-to-scientific-reports/xyrztqvdccns and click "open as template")

Try to use mouse gesture (two finger scroll) in the editor window


Actual results:

The window scrolls briefly and abruptly stops. Further attempts don't work.


Expected results:

Scrolling should be smooth. (There's no problem in chrome)

Comment 1

[Rares Doghi, Desktop QA]

Hi, I tried to reproduce this issue on Firefox 64.0 and Firefox Nightly 66.0a1 (2018-12-26) but without any success, I tried on a Touchpad with a 64bit Windows 10, as well as on a Notebook with both Windows 10 64bit and 32bit and still no luck, I feel like I'm Missing some steps because I can scroll in both Editor and Preview windows without any issues.

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

Or maybe try our latest Nightly build https://nightly.mozilla.org/ and see if the issue still occurs there.

Comment 2

[Rares Doghi, Desktop QA]

Could this be a duplicate of Bug 1516248 ?

Comment 3

[sorcererofdm]

Hi Rares,

I just tried safe mode, and it still doesn't work. I'm having this issue on a maxed-out surface book 2.

Just making sure, you are testing two finger scroll right? Not scrolling wheel of a mouse, or pulling the scrolling bar on the side manually.

Two finger scroll works in general but just not in overleaf.com, so it's not a duplicate of Bug 1516248.

Comment 4

[sorcererofdm]

Just to confirm, I am using Firefox 64.0.

Comment 5

[Rares Doghi, Desktop QA]

Hi, so I can't reproduce this issue on a normal laptop or a Touchpad Surface Pro and we do not have the Surface book 2 available for testing, I will set the component for this one to Core - Event Handling but in case its not the correct one please change it to a more suitable component.

Also sorcererofdm Can you try other devices, Laptops that have a multi-gesture trackpad in order to test this issue on your end as well?

Comment 6

[Hsin-Yi Tsai (she/her) [:hsinyi]]

I have a surface book 2. Will try to get back with the testing result soon.

Comment 7

[Hsin-Yi Tsai (she/her) [:hsinyi]]

I saw unsmooth two-finger scrolling in "Source" tab both on Surface book 2 with Firefox 64 and ThinkPad X1 with FF 66.
I however didn't encounter smoothness problems in "Rich Text" editor.

Dear reporter,
When you mentioned "editor window", did you mean "Source" or "Rich Text" or both?

Comment 8

[sorcererofdm]

"Rich Text" works somewhat, with smooth scrolling but rendering is a bit slow. But my problem is mostly with "Source." It looks like you confirm my report.

Comment 9

[Hsin-Yi Tsai (she/her) [:hsinyi]]

Hi :kats, I got impression that you know two-finger scrolling implementation. Could you please take a look at this and suggest next steps? Thank you.

Comment 10

[Kartikaya Gupta (email:[e-mail])]

Two-finger trackpad scrolling on Windows is usually turned into wheel events by the OS or driver. In Gecko we just handle it as wheel scrolling. That being said, from the STR, it sounds like it's not a problem with the widget-level events because the same gesture works on other pages.

Can you check if the bug happens with APZ off? (layers.async-pan-zoom.enabled to false, browser restart required). If so then it would be good to look at event handlers on the page and see if any of them are doing a preventDefault() on the wheel events. If it only happens with APZ on then it might be a bug in APZ hit-testing or event handling codepaths.

I probably won't have time to look at this myself this week and I'm off for two weeks after that but I can help you narrow it down at least.

Comment 11

[yuguorui96]

As far as I know, this bug only occurs in the overleaf's "Source" tab, "Rich Text" works without a problem.

In fact, on my XPS 9350, not only the touchpad scroll gesture triggers this bug, but also the mouse. If you scroll your mouse slow, you will find scroll is working, but if you scroll it relatively fast, it will not move at all.

Moreover, this bug can reproduce both on clean-installed Windows 10 17134 and Windows Server 2016. Also, I have tested with APZ off(with a restart), this bug still exists. However, this bug does not exist in Linux and Mac.

Also, I have checked the JS code in the overleaf.com, but there is no suspect code, the CPU usage is normal when you scroll the page.

I have been troubled for a long time before I thought it was just my case.

So, anything I can do?

PS: I am a student from Peking University, China. I hope to join the Firefox development team! LOL