The screenshots below display 1920x1080pixel widget button.
First one with Default DPIScaleCurve shows extra borders on the right and bottom.
Next one with more precision shows no extra boundary.
This is because UIScaleCurve in BaseEngine.ini lacks precision.
Changing this value from 0.666 to 0.6666666 will fix this problem.
1. open DPIScaleTest.zip[Image Removed] on UE4.25
2. Play standalone
3. See extra borders on the left and bottom
4. Quit standalone game
5. Open a project setting in menu
6. Find DPICurve and set the value of the key at 720 to 0.666666
7. Play standalone
8. Make sure there is no extra border
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-93923 in the post.