This issue has been closed as 'Won't Fix' due to an extended period of time without updates. If this issue is important to you please let us know by posting on the AnswerHub or UDN, and Epic will re-open the ticket for further review.
The Resolution Scale Slider in the Engine Scalability Settings does not adjust any settings unless your first adjust the r.ScreenPercentage.Editor variable.
Also reproduced in Main - Promotable - CL - 2614839
RESULTS: Screen Resolution changes after console variable is entered and again afterward by the Slider
EXPECTED: Should not have to enter an additional variable to use slider.
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