New releases: improving accessibility in the myst theme

We’ve shipped new versions of mystmd and myst-theme! A key part of this release was improving several key ADA accessibility concerns surfaced by an audit from Silas at UC Berkeley. As part of this effort, we’ve also got a new accessibility statement for Jupyter Book and MyST:

• https://jupyterbook.org/accessibility

• https://mystmd.org/guide/accessibility-and-performance

Read below for some of the bigger improvements and fixes that we made. Don’t forget that accessibility bugs are treated like any other bug - please report accessibility issues! We track them under the a11y label in myst-theme and in mystmd.

Improvements we made¶

Most of the recent fixes landed in the default myst-themes, which are the out-of-the-box web themes that come with mystmd and Jupyter Book:

• Keyboard access for scrollable content. Code blocks and cell outputs that scroll horizontally are now focusable with the keyboard, as are equations and text-based cell outputs.

• Color contrast in terminal output. The ANSI renderer for executed cell output now supports a fuller color palette, and we restricted the default palette so colored text meets contrast requirements against both light and dark backgrounds.

• Reflow at small viewports and high zoom. Wide tables no longer overflow the page, and the navbar grows in height when content needs more room.

• The search dialog is more screen-reader friendly. We improved ARIA semantics on the “search popup” so screen readers announce it correctly.

We also shipped a few user-facing changes unrelated to accessibility!

• Strict no longer force-checks links. Strict mode now skips link checking so that it is faster and more reliable. This was causing a bunch of users to slow down their builds, but now you’ll need to explicitly pass --check-links to ensure links are checked.

• Execution with multiple kernels is more stable. We fixed a race condition where Jupyter kernel connections weren’t fully closed before the next request came in, which could cause intermittent failures when executing notebooks across multiple kernels.

Upgrade¶

Simply run myst clean or delete the _build folder and the next time you build with myst or jupyter-book, the new theme will be downloaded. For the latest mystmd, you can run:

npm install -g mystmd
# or
pip install -U mystmd