In some cases, the IDE can not recognize the types of variables. To solve this problem, I've added comments in some places.
And I added comments for the following methods
Add missing comment for method GenericHeader::fromString
Add PHPDoc @return comment for Smtp::setUseCompleteQuit() method
PHPDoc @return comment does not apply to the constructor because remove this comment for Address::__construct
Add Mime\Message type for Mail\Message::$body property.
In some cases, the IDE can not recognize the types of variables. To solve this problem, I've added comments in some places. And I added comments for the following methods