Cannot receive all new message when two messages come at the same time

[quanvn1206]

Describe the bug
When I use folder-> idle() to get new message
and I sent 2 email at same time.
In mail client I get 2 mails. but in idle() function only last email received

Code to Reproduce
The troubling code section which produces the reported bug.

  $this->folder->idle(function($message){
                $this->onNewMessage($message);
            });

Expected behavior
Idle() function can receive all emails when they come at the same time.

Desktop / Server (please complete the following information):

• OS: Ubuntu 20.04
• PHP: 7.2
• Version v2.4 and v 4.1.2
• Provider Gmail