Start an IPFS daemon locally, then run with
npm install . && npm run build && python3 -m http.server 8081
and point your webbrowser to localhost:8081 and press the button.
When I do this, I get the following error printed on the IPFS daemon:
ERROR commands/h: err: http: invalid Read on closed Body handler.go:285
and the response does not include the hashes for all the files or the enclosing directory.