Type about:addons<enter> in the address box to open the Add-ons Manager. Hot key; <Control> (Mac=<Command>) <Shift> A)

On the left side of the page, select Appearance or Themes. Then select Default or System theme — auto. Now restart Firefox.

Pages are still dark when I enable the theme I had earlier today.

You can change this pref on the about:config page from 3 to 2 to revert to the Firefox 94 behavior.

• layout.css.prefers-color-scheme.content-override
  Dark (0), light (1), system (2) or 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.

• https://support.mozilla.org/en-US/kb/about-config-editor-firefox

See also this pref:

• ui.systemUsesDarkTheme [0:light; 1:dark; 2:no-preference]
• 1736218 - Add some sort of UI to select content dark theme preference

Chosen solution works. Dark pages (blank) still load prior to web page loading in light. Some drop down boxes are still black but guess I'll just have to live with that.

Chosen solution works. Dark pages (blank) still load prior to web page loading in light. Some drop down boxes are still black but guess I'll just have to live with that.

Yes, if your toolbar theme has light-colored text on the background/inactive tabs, it's normal for right-click context menus and toolbar drop-down panels to have light text on a black background. If it becomes too annoying you could consider changing your theme.