You can use BroadcastChannel [1] to communicate between tabs. It works well and does not require service workers. It's used in Tracim [2], for some reason we co

You can use BroadcastChannel [1] to communicate between tabs. It works well and does not require service workers. It's used in Tracim [2], for some reason we could not move to HTTP/2 at the time I was working on this project so we indeed learned about this connection limit soon enough… Even on HTTP/2, I believe it's best avoid sending 6 times the same message to the user just because they opened 6 tabs. It's less wasteful both for the server and the client. [1] https://developer.mozilla.org/en-US/docs/Web/API/BroadcastChannel https://developer.mozilla.org/en-US/docs/Web/API/BroadcastCh... [2] https://github.com/tracim/tracim/blob/develop/frontend_lib/src/LiveMessageManager.js https://github.com/tracim/tracim/blob/develop/frontend_lib/s...