We are currently unable to use filtering or Search functions with our Customer Expert field on the Accounts Table in our Prod and Dev instances of Service Now.
When we try to use a filter with this field it just blanks out when we Run it.
Search Functionality is Greyed out.
Since the Customer Expert field is of type "LIST" similar to the out of box "watchlist field where you cannot list search against.
In our documentation on "Search a list" it is stated that:
This search supports queries that include AND, but does not support OR. You cannot search in a column that uses the List field type, for example, watch lists.
If you would like to search this field in List view. You will need to change the type to something other than "List".