Filter Hook: Filters the group update notification message that will be sent to user.

Filter Hook: Filters the user email that the group invite notification will be sent to.

Filter Hook: Filters the user email that the group update notification will be sent to.

Filter Hook: Filters the group update notification subject that will be sent to user.

Filter Hook: Filters the subject for the friend request accepted email.

Filter Hook: Filters the message for the friend request accepted email.

Filter Hook: Filters the message for the friend request email.

Filter Hook: Filters the email address for whose friend request got accepted.

Filter Hook: Filters the subject for the friend request email.

Filter Hook: Filters the message that the notification uses upon successful registration with blog.