This is very limited and requires that you have memorised markdown. OK, that isn't too difficult and if that was the onlt problem I'd be happy with it and give it 4 stars.
My real problem with this system is that the Android app requires that I go through 2-factor authentication *every time* I synchronise. Therefore it is not possible to make a quick note or refer quickly to a note made on another platform. I do not understand this decision, the Firefox extension doesn't do this and it is unnecessary - if you want to offer this as an *option* for the paranoid and those that can't make their phone as a whole secure, fine, but please don't force it on everyone all the time.

La synchronisation entre appli smartphone et extension navigateur sur PC est aléatoire.
Accumulation d'historique "sur cet ordinateur".
De plus pour se connecter il faut entrer un code de sécurité transmis par mail même après entrée mot de passe. C'est très lourd pour un fonctionnement erratique.
J'utilise des mots de passe sécurisés, et il me faudrait vraiment une option pour supprimer cette connexion à deux étages totalement anti ergonomique sur un smartphone.
Soyez la solution pas le problème ;-)

It would be great adding multi-notepad and/or tree style notes

easy to use and sync's across :)

Schönes Addon! So kann man schnell simple, schicke Notizen erstellen, einfach während des Surfens. Kann mich nicht beklagen. Mozilla könnte das Addon aber ruhig mal wieder updaten!

Nice. Please change the colour of the icon in the sidebar, as it currently blends with the Dark theme background. Ability to create folders for notes would be great. Thank you.

Honestly really like it for quick notes. Can sync it up to phone as well which is handy. Plain and simple.

It's so simple and clean. I really love it. I use it during video conferences, shopping, everything.

Great start! It would be nice to open it in it's own window, have folders and pin notes for to-do and such. Sync to mobile would be great also. Thank you Mozilla!

It would be nice to have support for Markdown

Make please settings "check spelling" independent from general firefox settings.
I need the default spell checking in Firefox to be enabled, but disabled in this add-on. Due to the specific text, everything is underlined in red and poorly readable.