Lately we have been seeing more and more requests to utilize the "popover" feature in FileMaker 13. This functionality is great and provides a lot of opportunity to simplifiy interfaces. In combination with the "Hide Object" attribute the user experience can be dynamic and relative to the appropriate workflow for the user based on the state of the data.
But like anything new, too much is not good and everything in moderation. We have been getting requests to use popovers in portals which regardless of FileMaker indicating this is not a proper use of popovers we have been able to resolve the issues and make it work very well. However the issue that can come up is the management of data within the portal popover. If you need to just view and edit data that is visble on the portal popover that will work just fine. Where the challenges can come is in a more complex workflow where additional windows need to come up, you cannot use a popover inside a popover and it makes sense since you could create a popover headache if you could. So the question that we and of course you should ask when applying a popover into a portal is how will the data being shown be used. If you need to drill down futher but have to keep the user in the same context you are going to be far better off using Popup Windows and apply the appropriate window modes. The popup window will give you more control and give the user a better experience.