Ever since the upgrade to the latest Photoshop CC there are black bars around the edge of all projects, making things very frustrating and difficult to work with as it means projects are never centered and crops off elements when zoomed in.
What OS version are you using (looks like a Mac, but which version?)
Can you confirm that you're up to date with CC 2015?
Does this also happen in CC 2014?
Can you provide more screenshot examples of the behavior?
When you did the Upgrade, Did you also copy any third-party plug-ins over to the new version of Photoshop?