"Rendering Settings->Do Not Clear Scene" causes visual artifacts in editor panels

Setting Project Settings->Rendering->Optimization->Clear Scene to "Do not clear" prevents the scene from clearing even in editor window viewports, such as the Components tab of Blueprints and the Preview window of the Particle Editor (Cascade).

1: Set Project Settings->Rendering->Optimization->Clear Scene to "Do not clear"
2: Open the Components tab of a blueprint
3: Observe the viewport