Detecting a Click in the Corner of a Widget

I'd like a resizable widget that can server as a parent class for other widgets. [This forum post](https://forums.unrealengine.com/t/how-can-i-detect-a-click-near-corner-of-widget/1356428) describes my approach with pretty pictures of the blueprints.

My approach is when the mouse goes down in the widget, get the widget local coordinates of the mouse click, and see how near that is to the lower right corner, given by the function [GetLocalSize](https://docs.unrealengine.com/4.27/en-US/BlueprintAPI/UserInterface/Geometry/GetLocalSize/).

It works the first time, but not after the widget is resized.

I **don't** want to just stick a button or something in the lower right corner, since I'd like this resizable widget to be the base class of other widgets.