Private Browsing now uses a Dark Theme by default:
Set “browser.theme.dark-private-windows” = false to disable
Optionally to remove the new logo and indicator
Set “browser.privatebrowsing.enable-new-logo” and “browser.privatebrowsing.enable-new-indicator” = false
To disable the new Firefox View feature:
Set “browser.tabs.firefox-view” = false
Courtesy of @tannington of openSUSE forum.
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