Hi Nick,
Thanks for the very detailed write up regarding the colour contrast issues. We take the accessibility of the widgets seriously, and it’s my intention that we ship things that make Twitter accessible to all; we already worked hard to include solid support for ARIA live regions, text fallbacks and contextual abbreviations. Following your issue, we shipped an update to embedded Tweets and timelines yesterday that adopts your recommended colour adjustments for the offset text, so all text in the widget should now at least meet the 4.5:1 recommended ratio in the standard themes.
The update also fixes a couple of missing :focus styles, and cleans up the focus styles in general.
Finally: The issue also raises concern about the keyboard focusability of Tweet actions. We will try to further improve that at some point as well, but the existing behaviour is as follows, and since the actions are not core content I do not believe this should be a blocker in assessing your WCAG compliance.
• Tweets that can be expanded (either an ‘Expand’ link, or ‘View ’ link) display the actions statically in the expanded state where they can be focused.
• In browsers supporting touch events the actions are toggled to always display, with increased padding to aid finger tapping.
This leaves the case of Tweets that do not have stats or media, and do not have an ‘expand’ link. Here, actions must be accessed by visiting the Tweet permalink. This gap in immediate access is one that we’ll look to improve upon in the future.
Please let me know if you have any other concerns. It means a lot to me that we ensure content from Twitter is universally available.
Thanks,
Ben