622064 - new twitter text is greyscale anti-aliased and not sub-pixel

Status: RESOLVED INCOMPLETE

(Core :: Graphics, defect)

Description

[Asa Dotzler [:asa]]

all text on twitter.com (new version) is greyscale anti-aliased instead of sub-pixel anti-aliased and it looks really bad compared to IE9 and Chrome 10.

testing today's nightly build on windows 7 with:

Direct2D Enabled true
DirectWrite Enabled true
WebGL Renderer Intel -- Mobile Intel(R) 4 Series Express Chipset Family -- 2.1.0 - Build 8.15.10.2202
GPU Accelerated Windows 1/1 Direct3D 10

Comment 1

[Asa Dotzler [:asa]]

This is a very popular site that looks really awful in Firefox 4 compared to other browsers and compared to Firefox 3.6. I don't think we should ship with this kind of text display problem at such a major site so I'm nominating this to block.

Comment 2

[Boris Zbarsky [:bzbarsky]]

99% sure we have a bug on this already...

Comment 3

[Timothy Nikkel (:tnikkel)]

Bug 593604 or bug 612846 or bug 613040 or bug 603337, maybe.

Comment 4

[Asa Dotzler [:asa]]

(In reply to comment #3)
> Bug 593604 or bug 612846 or bug 613040 or bug 603337, maybe.

I'll bet it's bug 603337 based on a quick look at the stylesheet of newtwitter that includes many instances of both border-radius and overflow:visible.  That would mean this is actually a dupe/dep of my bug 613040. 

Should I dupe or dep?

Comment 5

[Asa Dotzler [:asa]]

Hrm. Twitter still looks grayscale aa to me, even after other grayscale aa problems were fixed by bug 628745

Comment 6

[Timothy Nikkel (:tnikkel)]

Asa, can you give me the URL for an example page on which you see this? (Even if you see it on every page.)

Comment 7

[Timothy Nikkel (:tnikkel)]

I took a look at some twitter pages (whiled signed in), and all the text I saw was was subpixel AA (screenshot -> gimp -> zoom in).

Comment 8

[Asa Dotzler [:asa]]

Attachment: screenshot showing grayscale aa at new twitter

Visited https://twitter.com/#!/mozillapeople/awesome and zoomed in using Windows 7 Magnifier app.

Comment 9

[Asa Dotzler [:asa]]

Sorry, I should have noted that I was logged in when I visited that page.

Comment 10

[Asa Dotzler [:asa]]

OK. I narrowed it down some. I see this grayscale aa on all newtwitter pages until I select a tweet (which shows the tweet and context in the right column area thing) and then everything becomes magically sub-pixel aa

Comment 11

[Asa Dotzler [:asa]]

even more info:

it goes back and forth as you open and close a tweet (into that right-hand area). I can zoom in using Magnifier.exe and click it open and closed and watch the whole page go from sub-pixel to grayscale and back with every click.

Comment 12

[Asa Dotzler [:asa]]

Attachment: twitter in both states, sidebar open and sidebar closed.

You can see here the difference between twitter when the tweet is selected and when it's not.

Comment 13

[Timothy Nikkel (:tnikkel)]

(In reply to comment #8)
> Visited https://twitter.com/#!/mozillapeople/awesome and zoomed in using
> Windows 7 Magnifier app.

I only see subpixel AA on that page while logged in with a tweet clicked on or not in Linux.

What happens if you change you hardware acceleration settings (d2d, d3d9, d3d10)?

Comment 14

[Asa Dotzler [:asa]]

Dammit. Now I can't reproduce. I swear it was busted. The screenshots don't lie ;-) 

I suppose we can mark this Fixed and I'll keep an eye out in case it comes back.

Comment 15

[Asa Dotzler [:asa]]

OK. This is gonna sound crazy, but I can reproduce it intermittently and I can also reproduce it in tab tiles, intermittently.  See http://grab.by/8Hxd and http://grab.by/8Hxi where the left tab is grayscale and then sub-pixel. Still don't know how to reliably reproduce but something's going on here.

Comment 16

[Asa Dotzler [:asa]]

I'm pretty sure what ever this bug is, the twitter and tab title issue is the same. Both switch back and forth between grayscale and sub-pixel.

When I can get a tab to go grayscale aa, and I hover over the Firefox button, it immediately returns to sub-pixel aa.

Comment 17

[Jeff Muizelaar [:jrmuizel]]

Asa, can you still reproduce this? I can not.

Comment 18

[(no longer active)]

Is there a good reason that this blocks betaN?  If not, it should be moved over to final+.

Of course, comment 17 suggests that this might be WFM now.  We need Asa to confirm.

Comment 19

[Asa Dotzler [:asa]]

I still see this but I cannot figure out why it's intermittent. Probably can't block on something we can't reproduce. Please don't resolve it, though, because I do still see this on current nightly builds on a clean profile.

Comment 20

[Mike Beltzner [:beltzner, not reading bugmail]]

There is no way that this would block final, Ehsan - messing around with code that affects font rendering. Given that fact, and the fact that we can't get a solid reproduction on this, I'm asserting that this isn't any sort of blocker for Firefox 4.

Comment 21

[Sid]

I'm getting this too on Win7 32-bit, but with hw-accel completely disabled (due to weak graphics).

Build 20110102 is the last with subpixel AA on twitter.
Since build 20110103 twitter has grayscale AA.

How can I narrow the regression window further?

Comment 22

[Sid]

An example of page is http://twitter.com/NASA
Blue links look especially ugly.

Comment 23

[Timothy Nikkel (:tnikkel)]

And you also checked in the latest nightly?

Comment 24

[Sid]

(In reply to comment #23)
> And you also checked in the latest nightly?

Yes, with latest nightly twitter is also grayscale.
Mozilla/5.0 (Windows NT 6.1; rv:2.0b12pre) Gecko/20110220 Firefox/4.0b12pre

Comment 25

[Timothy Nikkel (:tnikkel)]

Regression range for comment 21
http://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=a05e91710adb&tochange=c20f34eefa5d

Are you logged into twitter or not when the problem happens (if it makes a difference)? Which text is grayscale AA? Can you paste the graphics section of your about:support?

Comment 26

[David Bolter [:davidb] (NeedInfo me for attention)]

Asa does this bug still happen?