I've discover an issue while using google chrome, there is a scenario:

 

A using IE, B using google chrome.

1.   A start chat with B by clicking his name in the contacts and send a message. B did not receive a notification message (sometimes only a sound is heard only).

2.   B start chat with B using the same way, A did receive the notification and start the chart normally.

 

It seems to be fine if the target party is using IE but not chrome.

I suspect is the z-order of the notification is not correct or it does not display at all.

 

Please help, thanks.