Confirm that the code in Extension.js can all be found in `extension/src/components/App.js`. You can `arc patch` the proof of concept diff D14988 and build the extension there to confirm the logic here works. Can't test this here until we update the whole extension build script, which we don't want to do yet as we haven't implemented all the logic yet.
Test plan for diff that updates the extension build script will include integration tests for this functionality