This article is in need of a technical review.
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
onstksessionend property specifies an event listener to receive
stksessionend events. These events are notified whenever STK Session is terminated by ICC.
navigator.mozMobileConnection.icc.stksessionend = funcRef;
funcRef is a function to be called when the
stksessionend event occurs.
Not part of any specification.