Running the console command r.DebugSafeZone.Mode 0 does not disable all overlays.
The issue occurs when setting custom values in DefaultEngine.ini as well.
Tested using the following settings:
[SystemSettings]
r.DebugSafeZone.Mode=1
r.DebugSafeZone.TitleRatio=0.7
r.DebugSafeZone.ActionRatio=0.9
r.DebugSafeZone.OverlayAlpha=0.5
Tested in: 4.23.1 CL#9631420 4.25 CL#11341939
1. Launch project in a StandAlone window
2. Run console command r.DebugSafeZone.TitleRatio .7
3. Run console command r.DebugSafeZone.Mode 0
Result: The overlay is still visible after running r.DebugSafeZone.Mode 0
Expected: No overlay
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-89101 in the post.