[Forminator Pro] Adding "readonly" (or "disabled") to an input

Hello! I’m looking for a way to add “readonly” to an input (text) field that is not a calculation. It’d be badass if “readonly” was just an option added to any form field (#FeatureRequest).
Can you tell me if you already have an easy-ish filter I can hook into to add the disabled flag to my inputs? Or maybe to add my own readonly checkbox on the existing form field options, which then adds the disabled or readonly attribute to the field?