Rather than Broadcast Channel, you can use the Web Locks API (https://developer.mozilla.org/en-US/docs/Web/API/Web_Locks_API https://developer.mozilla.org/en-US

Rather than Broadcast Channel, you can use the Web Locks API (https://developer.mozilla.org/en-US/docs/Web/API/Web_Locks_API https://developer.mozilla.org/en-US/docs/Web/API/Web_Locks_A...). This handles the leader election pretty seamlessly because all tabs try to become the leader and only one actually can. This library (https://github.com/pubkey/broadcast-channel https://github.com/pubkey/broadcast-channel) from the fantastic RxDB javascript DB library uses WebLocks with a fallback to Broadcast Channel. But, WebLocks are supported on 96% of browsers, so probably safe to just use it exclusively now