As a user, I would like to have the option to select what type of notification the workflow validator provides.

Each option (old and new issue view) has pros and cons.

The old issue view provides a more invasive, noticeable, and easy-to-view notification. Also is possible to copy the error message easily.

The new issue view gives a more discrete pop-up, but is gone within a few seconds and is harder to copy/analyze. 

Having both options available to set on workflow/project/personal preferences would please all.

Other options:

• Disable auto dismiss pop-up.
• Option to "stick" the pop-up or to open the message on a permanent window.