How can I use the Prismic API filtering option to filter based on a value OR if that value is empty.
It seems that I can't combine "missing" and "any" into a single query, I get an empty result
I'm not sure you can combine "missing" and "any" directly in a single query. But you can work around it by doing two separate queries and then merging the results.
Unfortunately, this is not really feasible if we want to do pagination