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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.
Deprecated
This feature has been removed from the Web standards. Though some browsers may still support it, it is in the process of being dropped. Do not use it in old or new projects. Pages or Web apps using it may break at any time.
The Event.returnValue property indicates if the default action for this event has been prevented or not. It is set to true by default, allowing the default action to occur. Setting this property to false prevents the default action.
Use Event.preventDefault() instead of this non-standard method.
Syntax
event.returnValue = bool; var bool = event.returnValue;
Specifications
Although it was included in an old Working Draft of W3C DOM Level 2, this property is not part of any specification. Microsoft also has a description of it on MSDN.
Browser compatibility
| Feature | Firefox (Gecko) | Chrome | Internet Explorer | Microsoft Edge | Opera | Safari |
|---|---|---|---|---|---|---|
| Basic support | No support | (Yes) | 6 | (Yes) | (Yes) | (Yes) |
| Feature | Firefox Mobile (Gecko) | Android | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|
| Basic support | No support | (Yes) | ? | ? | (Yes) |