The many colors in recent Firefox themes make for dificult reading, especially if you have a vision disability.
How do I get plain black text and plain background in Firefox? Thnx.
Wšě wotmołwy (2)
Select Add-ons and Themes in the menu then Themes in the left panel. It seems the theme you want is Light. I know of two themes which you can install to change the toolbar colours to a light green. If you go to the add-ons site, look for 'solid' themes. https://addons.mozilla.org/firefox/
Easiest to fix this is to select a theme that has dark text on the tabs (toolbars) instead of light text.
You can change this pref on the about:config page from 3 to 2 to revert to the Firefox 94 behavior regarding to prefer dark or light background for webpages.
- layout.css.prefers-color-scheme.content-override [dark:0, light:1, system:2, browser:3]
You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.