Custom states can be aplied applied on form fields and it consist in a name and options. It's displaying a custom icon (set in options) and some specific style on the field.
If the EventOnCustomStateChange the EventOnCustomStateChange is set in designer, than everytime the every time the custom state is changed, the event is triggered and you can see the action (set or clear) and the customState that had been added/removed.
Custom states attributes:
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