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First run in new profile on touchscreen has broken wheel scrolling




2 years ago
2 years ago


(Reporter: kats, Unassigned)


46 Branch
Windows 10

Firefox Tracking Flags

(e10s+, firefox46 affected)


1. On a touchscreen windows device (I'm using a Surface with Windows 10 Pro), start Nightly with a new profile
2. Go to mozilla.org or any other website and try scrolling with an external mousewheel

Page scrolls

Page doesn't scroll. After closing and restarting the browser once the mousewheel works normally

On the first boot into a new profile, about:support shows e10s is enabled and APZ is supporting mousewheel input. On the second boot, however, e10s is disabled. Based on what :jimm said this is because the touchscreen is detected as accessibility and so the code to disable e10s on accessibility kicks in. However it seems to do it late in startup, after e10s and APZ are enabled, leaving them in some sort of half-enabled state. Restarting the browser keeps e10s disabled right from the beginning and so everything works fine.

According to :jimm I should also get a doorhanger about reduced accessibility support on the first start because of this, but I don't see that.

Comment 1

2 years ago
If I can reproduce I'll file a separate bug on the lack of a prompt for touch screens. Did you happen to check the console? I'm wondering if you see this message -
I don't see that message either in the browser console or the web console. I also don't see it in stdout, but nothing shows up there anyway. I didn't try attaching Visual Studio to get the console output - that would probably happen too late anyway.
tracking-e10s: ? → +
Hi Kats,

I am unable to reproduce this on latest Aurora (46.0a2-20160207004019) and latest Nightly (47.0a1-20160207030402). External mouse scroll correctly works when I start Firefox with a new profile.
Tested this on a Dell XPS 12 laptop (2in1) with the screen "detached" from keyboard. 

Is this still reproducible for you ? Maybe Surface tablet is a different environment than the Dell laptop and that's why I cannot reproduce it.

However, related to the doorhanger you guys mention, I only got it once on both browser versions. Created a new profile after to test it again and it no longer appears.
Also, regarding the about:support things, they work exactly as mentioned. First e10s and APZ for mouse scroll are enabled and after restart, e10s is disabled and "None" displayed for APZ.

Flags: needinfo?(bugmail.mozilla)
I'm unable to reproduce the mousewheel brokenness on latest m-c. Resolving WFM.
Last Resolved: 2 years ago
Flags: needinfo?(bugmail.mozilla)
Resolution: --- → WORKSFORME
See Also: → bug 1282846
See Also: → bug 1288751
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