Affected versions:

Nightly 92.0a1 (2021-08-04)

Affected platforms:

 MacOS11

Preconditions:

Have High Contrast Black(system settings) and dark theme(build settings) set.

Steps to reproduce:

1. Go to about:addons
2. Observe the left side of the page(sections side)

Expected result:

The text from the about:addons sections should be visible.

Actual result:

 The text from the about:addons sections  (Recommendations, Extensions, Themes, Plugins) text is not visible.

Hi Ralu, thanks for filing this (and really appreciate your use of both the access tag and the [access-s2] whiteboard, that helps us a lot) -- is this (attached screenshot) what you mean by the text isn't visible?

I'm able to reproduce this with the following settings:

System Preferences > Accessibility > Display > Increase contrast
about:preferences > Language and Appearance > Colors > Use System Colors