Moving an issue from one epic to another when an epic is selected makes backlog issues disappear

To reproduce you need to activate parallel sprints :

• create at least two epics
• create at least two sprints
• put some issues in each sprints
• drag some issues in each epics
• select an epic to filter the issues
• move one visible issue to another epic
• unselect the epic
• done, you shouldn't be able to see the backlog issues (and the others epics issues)