Laurențiu Nicola Reporter
	Description • 7 years ago

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:57.0) Gecko/20100101 Firefox/57.0
Build ID: 20170806100257

Steps to reproduce:

1. Disable smooth scroll and make sure e10s is enabled
2. Navigate to https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
3. Scroll using space or page down
4. Try the same on https://hackernoon.com/grokking-diesel-652cb8886a63


Actual results:

There is a "smooth" scroll effect on the page in step 2. Page in step 4 doesn't have that issue.

Opening the tab in a non-e10s window (from the right-click menu on tab) shows the same issue. Disabling apz.keyboard.enabled has no effect.

But after globally disabling e10s, the issue is gone.


Expected results:

Instantaneous scrolling if smooth scroll is disabled.

	Kartikaya Gupta (email:kats@mozilla.staktrace.com)
	Comment 2 • 7 years ago

(In reply to Laurentiu Nicola from comment #0)
> Disabling apz.keyboard.enabled has no effect.

Did you restart the browser after changing this? This pref change requires a browser restart. I can reproduce the issue you describe, but when I restart after disabling apz.keyboard.enabled, the behaviour is fixed (i.e. smooth scrolling option is properly respected).

	Laurențiu Nicola Reporter
	Comment 3 • 7 years ago

> Did you restart the browser after changing this? This pref change requires a browser restart. I can reproduce the issue you describe, but when I restart after disabling apz.keyboard.enabled, the behaviour is fixed (i.e. smooth scrolling option is properly respected).

You're probably right. I just tried it and it works after restarting the browser. So APZ is most like the cause. Thanks for pointing that out.