It is https://github.com/espruino/BangleApps/tree/master/apps/widbt_notify
In https://github.com/espruino/BangleApps/blob/master/apps/hworldclock/app.js I got the remove handler.
@Hank started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
It is https://github.com/espruino/BangleApps/tree/master/apps/widbt_notify
In https://github.com/espruino/BangleApps/blob/master/apps/hworldclock/app.js I got the remove handler.