Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.
The code read-only property of the DOMException interface returns one of the legacy error code constants, or 0 if none match.
This field is used for historical reasons. New DOM exceptions don't use this anymore: they put this info in the DOMException.name attribute.