Since v7.0.2, Multi-Level Cascading Select supports ScriptRunner integrations.
In this section, you will find examples of how to use ScriptRunner for advanced MLCS functionality, along with a list of REST APIs available.
Useful tips:
Avoid yellow spaces
When you copy/paste the code below, please make sure to get rid of the yellow spaces (shown in this picture). They will raise a “Type checking error” in your console.
How to get option IDs
To get to know the custom field and the option’s IDs, in the custom field context configuration screen click on Edit Options and Export CustomFields.
This is a sample JSON file with the information you are looking for: