Two screens, one film
Load the same movie file both of you already have. We'll keep play, pause and seeking in sync — plus live captions and a real-time audio analyser, right in the browser.
Both people run this same page, pick the same movie file locally, and enter the same room code. Nothing is uploaded — only small timing messages pass through the sync server. Captions and the audio analyser run entirely in your browser. Deploy watchparty-server (included) so sync works across the internet, not just shared WiFi.