Sprint Not Editable When Filter Retrieve Issue From Project Not Included In Board

Step to reproduce:

1. create 2 projects . TSTB and TSTC
2. create mutiple issues for each project
3. label one of the issue in project B with "DONE_BY_TSTC" . screenshot TSTB-1.png
4. create Scrum board . Refer CreateBoard.png . Result is shown in Board1.png
5. edit the Filter for this board to use

   project = TSTC OR labels=DONE_BY_TSTC ORDER BY Rank ASC

   refer to screenshot FilterTab1.png and Filter1.png and ProblemFilter.png

6. go to Agile tab, the sprint is not editable. refer to screenshot SprintProblem.png

Basically, when the filter returning issues which are not included in the project board, the sprint is not editable.

To workaround this problem, edit the board filter and use:

project = TSTC OR (project in (TSTB) AND labels=DONE_BY_TSTC) ORDER BY Rank ASC

Refer to screenshot WorkaroundFilter.png