455835 - make sure the message header pane works with a11y themes

Status: RESOLVED FIXED

(Thunderbird :: Message Reader UI, defect)

Description

[Aaron Leventhal]

There is a new theme for the message headers in Thunderbird.

The gray on blue color contrast for the labels is definitely too low. Even I with nearly perfect vision need to squint to make out from/subject/to/date. There's no chance for a lower vision person or a senior to make this out.

Here's a free color contrast algorithm and software analyser:
http://www.paciellogroup.com/resources/contrast-analyser.html

In addition, hardcoding the color into the theme is a section 508 violation. We need to follow the user's theme when they are using a special high contrast theme. You can use colors for nice effects but only when the user isn't setting that flag.

See http://www.access-board.gov/sec508/standards.htm
(g) Applications shall not override user selected contrast and color selections and other individual display attributes.

You can tell if the "high contrast theme" bit is set via
nsILookAndFeel::eMetric_UseAccessibilityTheme
http://mxr.mozilla.org/seamonkey/source/widget/public/nsILookAndFeel.h#206
In fact when that's set we automatically select the theme "classic", which is always supposed to obey the system colors. In that way you can make a special theme which uses fancier colors, but keep "classic" basic. The switch is here:
http://mxr.mozilla.org/seamonkey/source/chrome/src/nsChromeRegistry.cpp#603

I think the Firefox theme folks may have found another way around it, so that you can use more interesting colors than just the system colors.

But, no matter what you do, don't use gray on blue like that. Difficult to read for many people!

Comment 1

[Mark Banner (:standard8)]

Please see bug 455801 (including the URL on that bug) - we know there are improvements we need to make here, and the current version isn't the final version.

As there's useful info here, leaving open and marking dependent so it doesn't get lost.

Comment 2

[Dan Mosedale (:dmosedale, :dmose)]

We'll tentatively try and get this for beta 1, but there's some risk we'll end up relnoting and fixing it after beta 1.

Comment 3

[Bryan Clark (DevTools PM) [:clarkbw]]

Attachment: message reader w/ tango colors

I did an alternate look the other day that uses the Tango palette ( http://tango.freedesktop.org/Tango_Icon_Theme_Guidelines )

However I think it's probably a little too late to move towards this, however I want to think about lighter header background colors with darker text.

background-color: #eeeeec
header text: #2e3436
header label: #888a85

The label / bg colors don't pass all the tests on the contrast tester, however it is much closer.

Comment 4

[David Ascher (:davida)]

attachment https://bugzilla.mozilla.org/attachment.cgi?id=339386 shows the proposed theme for b1, with grey levels picked using the contrast tool.  Thanks!

We need to investigate what to do about the high-contrast theme bit, as AFAIK Thunderbird doesn't have such a theme ("pinstripe" and "qute" only in trunk, not sure if 2.0 was the same).

Comment 5

[Magnus Melin [:mkmelin]]

That looks much better!
Re the high-contrast theme, as i understand it it's not necessarily a *thunderbird* theme, but you enable a high-contrast theme on the system level, and the idea is that thunderbird should pick up on the system settings. (xref bug 417238/bug 382299)

Comment 6

[David Ascher (:davida)]

How can we get people to tell us what problems there are w/ system-level high contrast themes on the various OSes?

Comment 7

[Dan Mosedale (:dmosedale, :dmose)]

Post to m.d.accessibility, though presumably if Marco or Aaron were to blog something, that would get broader pickup.

Comment 8

[Bryan Clark (DevTools PM) [:clarkbw]]

taking and bumping to b3.

Comment 9

[Bryan Clark (DevTools PM) [:clarkbw]]

in linux this should be fixed bug 456829/bug 461098

I was a little worried about the gray text not giving enough contrast so I changed it away from the CSS system color.

Comment 10

[Bryan Clark (DevTools PM) [:clarkbw]]

bug 461098 landed today, if you can check out a nightly release later tonight and update this bug.  Thanks.

Comment 11

[Bryan Clark (DevTools PM) [:clarkbw]]

Firefox is doing an interesting hack here for detecting the default windows theme that allows them to style windows in a nicer manner if the default theme is running and then fallback to css system colors otherwise.

checkout:
http://mxr.mozilla.org/firefox/source/browser/themes/winstripe/browser/browser-aero.css

If we have the time for working on this it would be nice to follow firefox and do the right thing here.

Comment 12

[Bryan Clark (DevTools PM) [:clarkbw]]

I believe this is fixed.  On Linux we're back to using css system colors everywhere such that it picks up from the system theme change for high contrast.  Mac has a different (and much better) system for doing this.  Windows uses a "theme" like system but the colors haven't been touched AFAIK.  If we wanted to have a different set of colors for windows and a more accessible theme we could use what I found in comment 11

Comment 13

[Firefox Bug Husbandry Bot]

https://bugzilla.mozilla.org/show_bug.cgi?id=1527381