Share a browser tab and let someone else control it, on any site.
Co-Op is a Chrome extension for real-time co-browsing with genuine remote control. The host shares a browser tab as a peer-to-peer video stream. The guest watches it live and can take control - moving the cursor, clicking, scrolling and typing on the host's machine. Control is injected as trusted input via the Chrome debugger protocol, so the page cannot tell it is remote: it works on banking portals, canvas apps, paywalled pages and everywhere else that normal automation and screen-share tools fail. The architecture is pure peer-to-peer. The server handles signalling only and then exits the data path, so video never touches your infrastructure and bandwidth costs do not scale with usage. That is the moat. What's included: Chrome MV3 extension (vanilla JS, no build step) - popup session UI, offscreen WebRTC, host-side control injection, guest viewer and overlay Node + Express + Socket.io signalling server with Redis-backed rooms and MV3-resilient rejoin Full documentation: architecture, setup, testing, and a living decision log VPS deployment setup (PM2, Nginx, Let's Encrypt) Built with: vanilla JavaScript (ES modules, JSDoc types), Chrome MV3 + Offscreen Document, chrome.tabCapture, chrome.debugger (CDP input dispatch), simple-peer / WebRTC, Node.js, Express, Socket.io, Redis, PM2, Nginx. Current state: working end to end - the host shares, the guest sees the screen and controls it, with host-overrides-guest authority and pause/resume. Visible remote cursors and a redesigned popup are done. Honest list of what is left: click alignment drifts at the edges on non-16:9 windows, ICE restart needs verifying on a real network switch, and accounts/billing are stubbed rather than built (Google Sign-In and Lemon Squeezy were the plan). Sold as-is: full source and documentation. Pre-revenue, no users or infrastructure to transfer.
Project details
Next step: <p>Nearest finish line: fix the edge-alignment drift on non-16:9 windows, confirm ICE restart on a real network switch, add sign-in and billing, and ship to the Chrome Web Store. The hard part - trusted remote control that works on any site - is already done.</p><p><br></p><p>Obvious markets: remote customer support and onboarding, where an agent needs to do the thing rather than describe it; internal IT help desks; tutoring and training; agencies walking clients through a tool. Any of these will pay for "show me" turning into "let me".</p><p><br></p><p>Because the video is peer-to-peer, gross margin barely moves with usage - the only fixed cost is a small signalling server. A buyer with a support or IT audience could put this in front of users quickly, and the codebase is documented well enough to hand to a contractor or an AI agent without a walkthrough.</p>
For sale
Asking price: $1,000 USD
What's included
Source code, All related data, All related design work
Also included: the full documentation set (architecture, setup, testing, and the living decision log), the signalling server and its deployment configuration, and the build-contract files that let an AI coding agent pick the project up cold. Not included: there is no domain, no social accounts, no email list and no customer data - none of these exist yet.
Reason for selling
I am busy with other projects and would rather hand this to someone who has time to finish and launch it than let it sit unreleased.
Project metrics
Average Monthly Visitors: Pre-launch
Average Monthly Revenue: Pre-revenue
Average Monthly Downloads: Pre-launch / New project
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