Create a local WiFi web connection for messaging to someone playing a game or watching a video, without having to shout at them.

NOT a chat function, a get your attention system.

Short messages maybe 25 characters max. ex. "Time for dinner", "Time to feed cats", "I need to talk to you." or just a flashing dot.

Having it be a simple web page hosted on the headset would allow any browser to be used from a phone or computer on the local network and if kept simple with no bells, whistles or decoration would use minimum resources.