Background Blur widget clips (incorrectly) when rotating or shearing

Background blur appears to clip incorrectly when being rotated. The area covered by the background blur appears to shrink as the widget is rotated

1. Open the editor
2. Create a new widget blueprint
3. Add a background blur to the designer tab
4. Set the blur strength to 100
5. Rotate the background blur
6. Compile and save
7. Open the level blueprint
8. Add the widget blueprint to the viewport
9. Notice that only a small section of the area covered by the background blur is actually blurred

Expected: The widget would blur the space covered
Result: The widget appears to clip incorrectly