When trying to filter by this custom field (for all it's values) I cannot see any tickets, though they are definitely a lot that answer this query's criteria.
When I updated the field (using the edit option) I could suddenly see it by filtering the new value.
Returning it to the old value works - now I see only the one ticket (but I have thousands).
re-indexing was made - didn't help. Any thoughts? How can I make JIRA see this field?!