The program connects to a browser that is already running. The browser must have a remote debugging port. By default the program starts a local test site and reads its home page, so it needs no internet.

The simplest way is the flag -start. The program then starts a headless Chrome on a free port, connects to it and stops it at the end. It looks for google-chrome, google-chrome-stable, chromium, chromium-browser, chrome and headless-shell on the PATH.

$ go run ./remote -start

To use a browser that you start yourself, start Google Chrome with a debugging port:

$ google-chrome-stable --remote-debugging-port=9222

Or start headless-shell:

$ podman run --rm --detach --publish 9222:9222 docker.io/chromedp/headless-shell:latest

Then run the program from the root of the repository:

$ go run ./remote

The flag -url sets the URL of the browser. The default is ws://127.0.0.1:9222. Do not use it with -start.

$ go run ./remote -url ws://127.0.0.1:9222

The flag -nav sets the page to read. The default is the home page of the local test site. The local site listens on 127.0.0.1 of this computer, so a browser in a container cannot reach it. Give such a browser a page that it can reach with this flag. The program then does not start the local site.