This summary is not the rule. The rule text controls.
This rule covers situations where a court order affects someone who isn't officially part of the lawsuit. It says that even if you're not a named party in a case, you can still have legal rights or responsibilities tied to a court order made during that case.
If a court order is made in your favor, but you're not a party to the case, you can still enforce that order. You can use the same legal tools and processes that an actual party would use to make sure the other side follows the order. The one exception is if you're a creditor in a divorce case, that situation is handled differently.
The same idea works in reverse. If a court order requires someone to do something, and that person isn't a party to the case, they can still be forced to comply. The court can use the same enforcement methods against them as it would against an actual party to the lawsuit.
Basically, this rule makes sure that court orders can be enforced fairly, even when they involve people who aren't formally listed as plaintiffs or defendants in the case.