I didn’t class this as a Feature-Extension Request as I honestly don’t think it should be created as an extension and should more so be a built-in feature which is continuously improved upon in an open source sort of way and I’m certain email solutions such as ProtonMail and Tuntanota as well as others will support.
There are many encryption-on-the-fly solutions available on Firefox and Chrome which is difficult to deduce which one to trust in terms of security as the majority of them don’t seem to make any improvements and I’m sure there are more way of increasing privacy to the solutions they’ve developed but sort of neglected. I honestly don’t know what occurred to some of them when developing the same solutions
I’ve listed a series of third party email encryption solutions which I wish was really just one version of which is always optimally improved.
I figured as initially stated, if Brave would take a look at these solutions and incorporate a feature within Brave itself which offers a more practical solution for users not requiring a specific extension/addon for a particular email service and would instead be encrypted via the built-in email encrypting feature within Brave.
I personally think it is possible not that I can help in anyway but it would be unique and very privacy centric and would relate to the fundamental reason as to why you created the Brave Browser in the first place. It would be brilliant if you could contact the developers of the listed extensions regarding my suggestion.
The reason for the collaboration being that it could act similarly to VeraCrypt in that there aren’t really many free solutions that work as effectively and securely and is best considering they aren’t profiting from their developments if they could instead collaborate with the feature commendation.
Nevertheless, at the bottom I also included another possible solution for Brave to take a look at and would be interest in your views. One final thing I wanted to mention is that unlike all of the browser available in the world I you take on my suggestion I suppose Brave could also allow a BravePayments system for the free extention/addon whereby the developer can actually swiftly and anonymously get paid for their efforts. I suppose this can also encourage the developer alike to further develop their and other solutions within Brave. Thanks.
I also included a website link which maybe through financial support of the brave community or if you’ve got enough capital to fund it, the system below seems a rather simplistic solution for Brave to deploy if they allow it to be built into Brave to save time and not stressing much over improvements as they’ll take care of it.