This is really cool, and I'm excited to hear that it's making progress.

Binary transparency allows you to reason about the auditability of the JavaScript being delivered to your web browser. This is the first significant step towards a solution to the "JavaScript Cryptography Considered Harmful" blog post.

The remaining missing pieces here are, in my view, code signing and the corresponding notion of public key transparency.

Ok (let's pretend I didn't see the word "blockchain" there), but none of this should interfere with browser extensions that need to modify the application code.