Crash when dragging desktop shortcut to TLB Win 10

So the question becomes how was I able to initially have the TLB toolbar on the second display for a while after updating to Win 10??

The taskbar on the second monitor can't hold the toolbars

If that is not supported then how did I have it?

I don't know. I can guess you had the toolbar on the second monitor because of Ultramon. After updating Ultramon still thought it is on Windows 7 and create the own second taskbar.