Element: beforescriptexecute event

Non-standard: 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.

Warning: This event was a proposal in an early version of the specification. Do not rely on it.

The beforescriptexecute event is fired when a script is about to be executed. Cancelling the event prevents the script from executing.

It is a proprietary event specific to Gecko (Firefox).


Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("NameOfTheEvent", (event) => {});

onNameOfTheEvent = (event) => {};

Event type

A generic Event.


Not part of any specification.

Browser compatibility

BCD tables only load in the browser

See also