935852 - Scrolling creates blurriness

Status: RESOLVED DUPLICATE of bug 836430

(Firefox :: Untriaged, defect)

Description

[Ibai Garcia [:ibai]]

When scrolling in Mac OS X 10.9 text becomes blurry. This is particularly noticeable (and annoying) when you scroll really slowly.

I've tried to replicate on Chrome or Safari and the effect is not there.

Comment 1

[Stephen A Pohl [:spohl]]

Is this happening when scrolling past the top or bottom of the page, or does this happen when scrolling in the middle of the page? Is there a particular website that reproduces this issue?

Comment 2

[Ibai Garcia [:ibai]]

I've been doing some extra investigation and here is what's going on:

This happens when the site is scrolled horizontally. When scrolling vertically, and you slow down, (with a trackpad) Firefox tends to introduce some horizontal scroll that creates this blurriness.

You can check this out in almost any page, for example: http://www.nytimes.com/

Edge case, but fairly annoying.

Comment 3

[Stephen A Pohl [:spohl]]

Hmm, even with these steps I'm unable to reproduce this problem. Ibai, since you can reproduce this, would you mind running mozregression [1] to give us a better idea of when this was introduced? That'd be much appreciated! Thanks!

[1] http://mozilla.github.io/mozregression/

Comment 4

[Ibai Garcia [:ibai]]

Last good nightly: 2013-11-04
First bad nightly: 2013-11-05

It seems that we introduced something that allows you to move the page around....

Comment 5

[Stephen A Pohl [:spohl]]

Oh, are you swiping past the right or left end of the page? Then yes, you might actually run into history swipe animations (bug 678392). If you scroll to the left and keep scrolling when it becomes blurry, do you start seeing the previous page beneath it?

The blurriness will be fixed once bug 836430 lands, so assuming this is what you're seeing we can close this bug as duplicate of bug 836430.

Comment 6

[Ibai Garcia [:ibai]]

It happens in both directions.

Initially i didn't notice that i'm going over the edge, but you are totally correct.

Comment 7

[Stephen A Pohl [:spohl]]

Great, thanks for confirming!