There were changes around this feature in the July Hotfix.  Once you install this update, you will get a message when you generate a PO

"Skip displaying the new Purchase Order?   Yes or No?

When you select YES it prints the Purchase order Generation Register Report and that's it.  It goes back to the Sales transaction entry window.  So it's closer to what it did before on earlier versions.   If you select No, it prints like it did when you upgraded to GP2018. It opens the navigation list. 

Hello again! In Microsoft Dynamics GP 2018, the Purchase Order Generator will now automatically open the PO Transactions Navigation List Home page.  When you generate a Purchase Order from requisition.  Under Purchasing, select Transactions then click Requisitions.  After entering the requisition data, Click Actions at the top of the window, then mark Purchase.

In the Purchase Order Preview Window Click Generate, then Click Print.

Once you print the PO, the Purchase Order Navigation list will automatically open so the user can see the PO generated immediately without all of the other PO’s, so the list is filtered for the user.

Be sure to check back to the Microsoft Dynamics GP2018 Blog Schedule page to review posted blog articles and upcoming blog posts to help you prepare for all the great New Features in Microsoft Dynamics GP 2018.