Not sure if it's related, but I had some issues related with tiptap addExtension (not sure exactly) before, it was very weird but I fixed by detonating node_modules and installing again, maybe some conflict with multiple versions of tiptap being installed.
Discussion
It is exactly that, the type of Editor differs between versions. I tried pinning the same version that nostr-editor uses, but no luck. Tiptap/prosemirror is full of fun nuggets like this one.
Agree, it's a beast of a dependency, if you be able to share your rollup.config.js I might be able to help.
I think I've got the basic idea. In this case it was because I was using npm link to point to nostr-editor, which had tiptap 2.9.1 in its pnpm-lock, meanwhile my project (@welshman/editor) has tiptap 2.6.6 in its npm lockfile. I've synchronized the versions (to 2.10.4) and all is well.
lockfiles are evil