Bugzilla

Description:
Please provide an explanation of the feature or change. Include a description of the user scenario in which it would be used and how the user would complete the task(s).
Screenshots and visual UI specs are welcome, but please include sufficient accompanying explanation so that blind members of the accessibility team are able to understand the feature/change.

How do we test this?
If there is an implementation to test, please provide instructions for testing it; e.g. setting preferences, other preparation, how to trigger the UI, etc.

When will this ship?
Tracking bug/issue:
Design documents (e.g. Product Requirements Document, UI spec):
Engineering lead:
Product manager:

The accessibility team has developed the Mozilla Accessibility Release Guidelines which outline what is needed to make user interfaces accessible:
https://wiki.mozilla.org/Accessibility/Guidelines
Please describe the accessibility guidelines you considered and what steps you've taken to address them:

Describe any areas of concern to which you want the accessibility team to give special attention:

Description:
Within reader view, the text options and layout menu along with the color theme menu have been updated with a new UI and some additional features. The new features for the layout menu are the ability to adjust character spacing, word spacing, and text alignment. The theme menu has a new "Custom" tab that allows you to choose fully custom page colors. Users can access these features through the menu toolbar within reader view.

How do we test this?
Once this patch is landed, the new menus should be enabled by default in Nightly. You can test it out by visiting any text-heavy webpage and clicking the reader view button in the address bar. 

When will this ship? We are aiming to ship with Fx 129.
Tracking bug/issue:  Bug 1874981 

Design documents (e.g. Product Requirements Document, UI spec):
https://www.figma.com/design/BuurTXXqQjrikE0Dfvb5Wp/Reader-View-Comfort-Settings-Menu?node-id=232-559&t=0JaQjz3AJbmbsc00-0

Engineering lead: Irene Ni @ini
Product manager: N/A

The accessibility team has developed the Mozilla Accessibility Release Guidelines which outline what is needed to make user interfaces accessible:
https://wiki.mozilla.org/Accessibility/Guidelines
Please describe the accessibility guidelines you considered and what steps you've taken to address them:
Semantic markup was used wherever applicable, and I tried to use onscreen labels where possible. I tested to ensure elements have focus rings with keyboard navigation, and distinct hover/active states. Light and dark mode was tested with the accessibility inspector to ensure color contrast.

Describe any areas of concern to which you want the accessibility team to give special attention:
The slider reusable component used in the text and layout menu is new, so we want to ensure it is keyboard/screenreader accessible. The color picker components used in the Theme "Custom" tab are also new.