Here is two methods. It might sound inefficient to store the owner, but it’s potentially a better solution, because it may turn out the the outer is not the original outer, because it may have been reassigned to a different object out from under you. Less likely with widgets but still possible.
You can also specify the type if you set the owner on spawn like shown below, which could potentially avoid a cast if you only need one type of class.
Note: I’m just using UUserWidget because its easy, it could be any widget class. For the first method you should use either a base class all your widgets extend from so they can all call some “GoBack” method.