Boards stay empty if filter it on a milestone that contains "+"
Step to reproduce:
- Create a milestone with a "+" in its name.
- Associate few issue to this milestone.
- Create a new board and add a milestone filter.
- Select the freshed created milestone.
- Board stays empty.
To make it working:
- Rename the milestone and remove the sign "+"
- Display the board again.
- Board displays the issues.