Cassandrich@mcc@mastodon.social @leo@60228.dev No, it's very explicitly malicious.
mcc@dalias@hachyderm.io @leo@60228.dev Is it useful for a chat app to be able to notify the people you are talking to when you go offline?
khmit could be used for that, but chat apps generally already have service workers running to do notifications on the client side, so they typically use those to report presence changes.
besides which, the beacon spec mandates that the browser engine can coalesce beacons or deprioritize them, so they're not reliable enough for anything that might benefit the user.
it's a focused and purpose-built tracking mechanism and you lose nothing by disabling them.
CC: @dalias@hachyderm.io @leo@60228.dev