At the moment the only custom fields that can be used as placeholders are Insight custom fields and this feature would extend support for standard custom fields, like text fields
- In your Insight field configuration use an IQL that references a custom field that is not an Insight custom field, ie. SimpleTextCustomField - customfield_xxxxx
Your search results reflect the values in that custom field.
You don't get any results.
Set up an Insight field that mimics the value of that custom field, ie. an SimpleTextCustomField Insight field, and set that Insight field as the placeholder and also set up an Automation rule that populates that Insight field when the relevant custom field is changed.