On the twelfth day of NAVmas Microsoft gave me, Smart Notifications

You can now get in-context notifications when you create a sales invoice for a customer that has an overdue balance, for example, or when the amount in the sales document exceeds the credit limit specified for the customer. A subtle notification also shows up if you try to sell more items than you have in your inventory. Try to enter a large quantity in a sales invoice line, and see the notification kick in.

Notifications will be show to you in different areas of Microsoft Dynamics NAV, and it’s up to you if you react on them or ignore them.