Cascading fields for Atlassian Assets with multiple values

In a previous video, I showed how you can set up two custom fields for Assets, so the selection of the first field will act as a filter in the second field. This way, we can, for example, select a country in the first field and then show the cities based on the country selection in the second field. In this video, I show how you can expand on this so that if you select multiple options in the first field, you will also get a selection for both in the second field. It might seem like a simple change, but it is actually a bit tricky!