Firefox 95+ is taking more and more cues from your toolbar area theme for how to style other aspects of the browser. There is a setting for some of these, but not all of them. '''(A) Right-click context menus, toolbar drop-down panels''' Starting in Firefox 89, these would flip to a dark background if the text on the inactive/background tabs was white or light. Firefox 96 has extended this adaptation to more parts of the browser. As far as I know, the only built-in way to avoid this is to change your toolbar theme to one with dark text on the inactive/background tabs. (The other way is the not-officially-supported userChrome.css file route.) '''(B) Built-in pages, and websites that have light/dark responsive themes''' Starting in Firefox 95, Firefox would inform pages that you preferred a light/dark theme based on your Firefox toolbar theme instead of your system theme. I have attached a composite screenshot of how Firefox 96 renders the new tab page with a "Dark" theme (light text) and a "Light" theme. There is a way to decouple your page (content) theme preference from your toolbar theme. At this point, it's only available through the back door... (1) In a new tab, type or paste '''about:config''' in the address bar and press Enter/Return. Click the button accepting the risk. ''More info on about:config:'' [[Configuration Editor for Firefox]]. ''The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future.'' (2) In the search box in the page, type or paste '''layout.css.prefers-color-scheme.content-override''' and pause while the list is filtered (3) Double-click the preference to display an editing field, and change the value to whatever you prefer from the list below, then press Enter or click the blue check mark button to save the change. * 0 => Force a Dark background * 1 => Force a Light background * 2 => Follow the System theme (default in Firefox 94) * 3 => Follow the Browser toolbar theme (default in Firefox 95+) The about:config page should immediately reflect your saved change.