Hi,
I tried to use the addCustomFilter but it is not working.

No error being thrown, but when you click on the lookup field it will says the you have a invalid XML format

I am confident that my XML is correct. So my suspicion is that this error is being thrown because there are multiple tables inside the look-up field.
I tried to search about javascript filter to a multi-table lookup field but I can't find anything helpful on the internet.
Does anyone know how to do this? Thank you very much