You’re not mistaken, it is definitely possible with at least RSA, though, I would guess it may not always be possible. It also sounds like it’s still a bad idea unless you know all of the parameters used to generate the keys and can be sure what information is actually encoded in the keys.

As others have said, it’s quite good on privacy. For the truly paranoid, IIRC you can even self-host the sync server.

From the security perspective of privacy, do make sure to use a good password for the Mozilla account, the account password is also the encryption key for the E2E encryption.

Technically neither of these are donations, but:

I subscribe to Firefox VPN, and don’t actually even use it, just because I want to support them in a way where money could possibly towards FF dev and not just the Mozilla foundation (which can’t fun Mozilla corp work AFAIK).

I also have a supporter subscription at https://neocities.org because I support his ideals. Plus I get dirt cheap, easy to use static hosting out of the deal.

Edit: Oh, I guess humble bundle purchases might count, I do at least slide the sliders to make sure the charities get most of the money.

Edit 2: Oh and the Calyx Institute, that’s actually a proper donation to a registered nonprofit. With my $400/year donation I get a 4G hotspot with actually unlimited data. (They also have a $500/year for an unlimited 5G hotspot, I just haven’t felt the need to upgrade since they started offering that.) I also use CalyxOS, so it’s nice to feel like I’m supporting that.

Wait, what? What did he do? (Aside from selling the company, I mean.)

OP is asking about userChrome.css, which applies to the style of the browser window itself, not webpage contents. Websites can't view the markup for the browser window itself (which, fun fact is (mostly?) just HTML too), otherwise this would all be moot and they could just look at your list of tabs or your username in the menus.

I think you might have misunderstood something along the way. You don’t need to use Chrome to use Element. Element is a client for the Matrix federated chat protocol. It exists as a web app (that works just fine with Firefox), an iOS app, and an Android app (that’s available in F-Droid). You can also use any other Matrix client you want.

And if you want to use the same account, the only thing you won’t have access to is your past encrypted messages.

Element works without play services and has iOS & Android apps (plus web) and has a pretty friendly UI.

What is GP?

Probably ‘Google Play [Services]’.

without phone access?

OP doesn’t have access to the phone(s) to install & setup something for them.

The best way I know of is finding a device that’s supported by gadgetbridge: https://codeberg.org/Freeyourgadget/Gadgetbridge#supported-devices (be sure to check the warnings, some devices require you to pair with the OEM app first or possibly even keep the OEM app around)

Though, I used this with an Amazfit Bip and didn’t find the data particularity insightful. It often was just straight up wrong about whether I was sleeping or not. So, I too am curious to see what other answers come in.