Custom fields of the Multi Select type cannot be edited inline in List View

Steps to repro:
1. open the Card Configuration page
2. add a multi select custom field to the list view for any top-level issue type
3. open the Planning Board
4. hover the mouse over the area where the custom field you added in step 2 is displayed
5. click on the custom field value

Observed:
The custom field value cannot be edited.

Expected:
Multi select custom fields should be editable inline.