hello,
I use few multi-value controls in PBI and in Task work items (TFS 2012.2)
There a specific scenario that causes the multi-value control to stop working in the web access, the scenario is as following:

• go to the backlog in the web access
• create new PBI and double click to open the PBI form
• from implementation tab, create \ open new task (a new Task form is opened above the PBI form)
• update the task fields and click save & close (the Task from is closed and the PBI form is displayed again)
• try to update the multi-value field - in this case you can select values from the drop down of the control, but:
  1) the selected values are not being selected:
  
  usually, when selecting, the selected values are being displayed in the text box (red mark in pic.)
  2) the PBI form cannot be saved. the buttons are disabled
  

Is this can be fixed?
Thanks all,
Roy