FIX: problem when [] custom field is send (PR #13573)

Multiselect data can be saved but when all options are removed then data are not cleared

Ajax function is removing an empty array from request data. In that case, we should change [] to null.

We need that empty values to properly empty data.

GitHub

Will it be hard to test this? The fix looks OK to me at the code level but I don’t understand what possible values there are.

Will it be hard to test this? The fix looks OK to me at the code level but I don’t understand what possible values there are.

Added :slight_smile: