When console command r.HDR.EnableHDROutput = 1 is used, the entire engine UI becomes lighter or more washed out / desaturated, as shown in attached screen shots.
Confirmed this bug is not present in 4.16 or 4.17. This is a regression.
The gamma for the user interface appears to change when console variable r.HDR.EnableHDROutput is set to 1. Doing the same thing in 4.16 does not have the same effect. Did not test in 4.17.
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