Title is descriptive enough. My suggestion:Persistently dark themed private windows by default.Option to toggle dark theme in private windows on and off in Themes setting and/or Privacy settings.
When you turn on V2F in Firefox Account you are provided 8 recovery codes (to be printed, noted, whatsoever, and kept in a safe place) that can be used in case you have not access to your temporary codes generator app (Google Authenticator, Authy, Ae...
I don't think this is an appropiate idea in this forum, this is about Firefox products and how should the browser be, not about specific needs on it's AddOn ecosystem; eventhough, a need has been identified for addon developing.
Additionally, if a simple presenter view would be added to that reader, for example to be used with Beamer presentations, witch included a Clock/Timer/Countdown and slide splitting to be used in the way Pacien (GitHub https://github.com/pacien/beamer...