Even the popup window when you hover on the Lync/SfB program on your task bar seems to order the list by placing the most recent new IM session at the top, but as you see in the screenshot below, the tow lists don't exactly match up either.
|Skype for Business client - Tabbed conversations. |
Conversation window in the background, and the taskbar list when you hover on the client, in the foreground.
If anybody has found a way to sort either of these lists, please let me know :-)