cookies.OnChangedCause

The OnChangedCause type of the cookies API represents the reason a cookie changed.

Values of this type are strings. Possible values are:

evicted

A cookie has been automatically removed due to garbage collection.

expired

A cookie has been automatically removed due to expiry.

explicit

A cookie has been inserted or removed via an explicit call to cookies.remove().

expired_overwrite

A cookie has been overwritten by a cookie with an already-expired expiration date.

overwrite

A call to cookies.set() overwrote this cookie with a different one.

You can listen to the cookies.onChanged event to be notified when cookies change. The listener is passed a changeInfo object that contains a cause property, whose value is the OnChangeCaused string:

browser.cookies.onChanged.addListener(function(changeInfo) {
  console.log('Cookie changed: ' +
              '\n * Cookie: ' + JSON.stringify(changeInfo.cookie) +
              '\n * Cause: ' + changeInfo.cause +
              '\n * Removed: ' + changeInfo.removed);
});