I did some research on this and found that one possible workaround is to add an invisible Border behind the Button and use it to capture the mouse event. To make sure the Border remains invisible, you can set the A (Alpha) value of its Brush Color to 0.
I also found that, according to comments from the developers,the recommended approach is to use OnPreviewMouseButtonDown instead of OnMouseButtonDown. The main difference is that OnPreviewMouseButtonDown uses tunneling, while OnMouseButtonDown uses bubbling.
In simple terms, tunneling means the event travels from parent widgets down to child widgets, while bubbling means the event starts at the widget that received the input and then propagates back up through its parent widgets.
I also came across several older community posts discussing the same behavior, which I’ll leave below in case you’d like to take a look. While some of them are a few years old, they all point to the same solutions mentioned above.
