Just does not work, Ubuntu Impish, FF 100.0.1.

I actually never succeeded in installing this addon with firefox. Sad story.

I'm surprised to see this:
https://outgoing.prod.mozaws.net/
Why use this link in front of other links?
Two examples here:
https://outgoing.prod.mozaws.net/v1/f25582500f72007b6b5fe376d84fdf6185c21ee47d1ddc9a32275ab2f37f7404/https%3A//twitter.com/mailvelope
https://outgoing.prod.mozaws.net/v1/93377538754c52b39b6dbfee793e65c47f34f75a1f1f2b23d27da828005c99c7/https%3A//openpgpjs.org

Installation in Firefox 91.7 on Linux not possible. The installation fails without any error message.

I really wish the GnuPG/Linux would get fixed. This has been an issue for years.
"GnuPG is not available
Do you have GnuPG installed?"

Way too much hassle to try and get this thing working, which I was not able to achieve. A severe lack of instructions makes this a complete waste of Time. Uninstalled
Would give zero stars!!

It's all in German. Would not log me into my account, even though my gmx account is open in Firefox. So, I entered the correct email address and password.

Endlich einfache Verschlüsselungen über den Browser von jedem Gerät möglich

Waiting for Firefox for Android version. Please hurry!

After 30 minutes trying to import my already existing private key (didn't want to generate a new one), without succeeding, I decided to uninstall it. Maybe it's my fault, but I really couldn't find a way to do it.