Servo isn’t a full browser, it’s a tech testbed for Mozilla to test out their various rewritten Rust components. I wish they would have promoted it to full browser status, but I think intention was always to take pieces of Servo as they were completed and drop them into Firefox.
Ah, I see the confusion. Originally you mentioned two Proton services, password manager and email provider. The person who replied to you suggested two alternative password managers (one commercial, the other one FOSS). You then replied saying without a specific email feature it would be pointless, which would be fair for an alternative email provider but doesn’t apply in this case.
What do you mean by email aliases?
Hmm seems like it’s only partially true these days. Looking at their webpage they have a screenshot of their Wikipedia entry (why they didn’t just link to it I have no idea) that provides some more up to date info. It was a testbed and they mention a project Quantum where the tech was added into Firefox’s Gecko engine. In 2020 Mozilla laid off all their Servo devs and handed the project over to Linux Foundation Europe. It seems like since then they’ve reenvisioned the project as an embeddable rendering engine similar to WebKit or V8.
Edit: Further details available on the Wikipedia page. In particular this last paragraph seems highly relevant:
It seems like the ‘reboot’ is focused on turning it into a competitor for WebKit/V8. Looking at the projects roadmap it seems there are currently no plans in the works to make it a proper standalone browser.