Better not to support pasting private key into Iris and use window.Nostr.
Discussion
Hmm, I'd still like it to be a low barrier of entry way to try out Nostr. Maybe some notification that prompts to use extension, after you've used it for a while?
Unless you're on mobile, where extensions won't usually work. For Android I think PWAs can be actually packaged as "native" apps. Idk about apple, probably not.
Another option to easy theĀ entry way is to automatically generate a new keypair and later offer the option to the user to sign Key Delegation tokens if they want to post on behalf of another different privkey.