⭐⭐⭐⭐⭐Does what it says on the tin! Short and sweet codebase that’s easy enough to verify personally, and doesn’t ask for any crazy permissions.
I probably needn’t care about this validation: when I wrote a Thunderbird plugin to enhance integration with ProtonMail, I wrote it principally for myself: scratching my own itch. It was nice to see that (at time of writing) a few hundred other people have made use of the extension too, but it wasn’t essential. I’d be maintaining it regardless because I use it every day.
But it still warmed my heart to see a five-star review come in alongside a clearly-expressed justification.