Hi,
I was trying to figure out, whether there is an option to group issues in backlog by epics.
The desired look is similar to the Portfolio, where I see the list of epics, and when clicked, the list of sub-tasks (stories) is displayed.
Often, when I have a new idea, I create an epic, and later on, when we are going to develop the feature, we design the stories, but the epic is not visible in the backlog! so I end up creating a new one 
Actually, the epics are hardly visible, when we want to use the epic swimlanes in current sprint, which I think is very useful.
I would love to see my backlog grouped by epics, it would definitely improve the usability.
Thanks for your responses and time!