While I mostly agree with this, it is a very common convention to show additive text in green and destructive actions in red, when I saw the yellow blue version I have to look for a key to see what it meant, I worry that we're making the users think too much. You should have IMMEDIATE understanding of what the colors mean and not have to think too hard about it. While some users could see the red and green as a value judgement I think its common enough in diff views in other products that I don't think it will be an issue for most users, especially user new to the system, but familiar with the pattern elsewhere. 

second issue; colorblindness. The mediawiki.ui colors are actually tested against a color blindness simulator to make sure that the green has enough blue, and the red has enough orange to differentiate them. These colors were not arrived at accidently or on a whim. If for readability sake we choose to use a lighter shade of those colors we should make sure those values of the color are further tested against a color blindness simulator again. 

Jared Zimmerman  \\  Director of User Experience \\ Wikimedia Foundation               
M : +1 415 609 4043 |   :  @JaredZimmerman

On Tue, Apr 1, 2014 at 10:34 AM, Brandon Harris <bharris@wikimedia.org> wrote:

        My concern with red/green is (and has been) about the psychological implications of "green = good, red = bad".  Revisions are neither of those things:  sometimes removing things is better.  Sometimes adding things is bad.

        Revisions are neutral things.  I'd like us to try to find colors that support that principle.

On Mar 31, 2014, at 2:13 PM, Jon Robson <jrobson@wikimedia.org> wrote:

> We are considering changing the colours in the diff page view for mobile. Previously Vibha and Munaf had explored this (see results below). Have we run similar tests for the new colours on the diff page?
> ---------- Forwarded message ----------
> From: Munaf Assaf <massaf@wikimedia.org>
> Date: Thu, Mar 28, 2013 at 3:21 PM
> Subject: Diff views for the colorblind
> To: Jon Robson <jrobson@wikimedia.org>
> Cc: Vibha Bamba <vbamba@wikimedia.org>, Maryana Pinchuk <mpinchuk@wikimedia.org>
> Vibha and I tested these settings out and they work pretty well.
> <ColorblindDiffs.png>
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Brandon Harris, Senior Designer, Wikimedia Foundation

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