1300874 - [Intermittent] Stylus scrolling not working correctly [e10s]

Status: NEW

(Core :: Widget: Win32, defect, P3)

Description

[Kanchan Kumari QA]

Stylus scrolling not working correctly

[Tested Platform] 
surface pro (touch enabled)

Build ID  20160906030431
User Agent  Mozilla/5.0 (Windows NT 10.0; WOW64; rv:51.0) Gecko/20100101 Firefox/51.0


[Pre-Requisites] 
about:config settings:
javascript.options.asyncstack; false
browser.tabs.remote.force-enable; true
layers.async-pan-zoom.enabled; true 

about:support info
Multiprocess Windows 1/1 (Enabled by user)
about:support Asynchronous Pan/Zoom wheel input enabled; touch input enabled

[Steps to Reproduce]
1. Launch Firefox on Nightly 51.0a1 by double tapping the icon with Pen/Stylus.
2. Tap the Location bar and use the onscreen keyboard to type http://www.imdb.com/.
3. Scroll through the page using Pen/Stylus.
 
[Expected Results]
Scrolling should be smooth. Scroll bar should be updated.
 
[Actual Results]
Scrolling is not smooth. When scrolling down/up using stylus, it doesn’t scroll to correct location. When I drag down with stylus, it scrolls up momentarily and then suddenly comes back to some random position(mostly previous position in the scroll bar).

[Note]
I observed this issue with e10s. Without e10s, entire window shakes momentarily when stylus is used for dragging up or down for scrolling purpose. 
This is not reproducible with finger touch. 
Please pay close attention to vertical scroll bar on right side in the attached video.

Comment 1

[Kanchan Kumari QA]

Failed to attach the video. Please see video here: https://ranisharma22.tinytake.com/sf/OTU1NjA1XzQwMDY1OTU

Comment 2

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

Hm, I think I might have a different stylus than you - I'm not able to scroll at all with my stylus, it only does text selection. In your video I see a little arrow appear near the stylus point, and I don't get that at all.

Regardless this seems like a windows widget issue to add proper stylus support, doesn't seem related to touch specifically.

Comment 3

[Jim Mathies [:jimm]]

(In reply to Kartikaya Gupta (email:[e-mail]) from comment #2)
> Hm, I think I might have a different stylus than you - I'm not able to
> scroll at all with my stylus, it only does text selection. In your video I
> see a little arrow appear near the stylus point, and I don't get that at all.
> 
> Regardless this seems like a windows widget issue to add proper stylus
> support, doesn't seem related to touch specifically.

The stylus should generate mouse events, although when dragging a page I'm not sure what happens. needs investigation.

Comment 4

[tunepunk]

Just saw this issue. Can you please make sure there is an off switch for stylus scrolling. It can break drag and drop, web apps with drawing functionality, and other web-app features. To be free of this this anti-feature "stylus scrolling" is the main reason I'm using Firefox.