Thanks for the link; I wasn't familiar with Magical.

From what I can see, Magical focuses on general autofill, while Injectless is exploring a more declarative, least-privilege approach, where each site explicitly defines which fields it can expose and on which domains, with domain-level validation and explicit user control.

Even so, comparing UX, adoption, and technical trade-offs with products like this is exactly the kind of signal I was looking for.