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.
reason is a read-only property that indicates the reason the call is being forwarded.
var reason = instanceOfMozMobileCFInfo.reason;
Return a number.
The value is equal to one of the
MozMobileCFInfo.CALL_FORWARD_REASON_* constant values.
Not part of any specification.