Cascading Choice in a custom field, both single choice and multiple choices, cascading beyond 2 levels

[#1]

Allow for cascading selections:

Example: User selects Country then 2nd dropdown box shows only States that apply to that Country

[#2]

This is similar to one I put in without realizing yours existed (oddly, the search didn't turn yours up...):

https://support.workfront.com/hc/en-us/community/posts/360026346574-Hierarchical-Cascading-Matrix-Fi...