Simple HUD in Topdown template will have rendering errors if played in Immersive mode

Simple HUD in Topdown template will have rendering errors if played in Immersive mode (F11). It will cause a white flickering line on the left and top of the window that will start to blur as the player moves around. A blurred box will appear in the center of the screen after a few seconds of moving.

Any rendering artifacts will disappear if the UMG widget is deparented. Additionally, the artifacts will only appear if the immersive-mode window is the only editor window being rendered. Opening any other window will fix the issue.

1. Download the attached project > Unzip > Open the .uproject file
2. Once opened, Play-In-Editor
3. Ensure any other editor windows are minimized or closed
4. Click to move the character around
5. Press 'F11' to enter Immersive mode
6. Continue moving the player

Results: A white flickering line will be present on the left and top of the screen. Move the character for several seconds more and you will see blurring/lens flare spread on the screen.

Expected: For Immersive mode to be identical to PIE or any other play mode.

Canvas problem

Scene capture 2d component potential bug

[Repro Included] [4.7] Artifacts In Viewport in Fullscreen PIE

[4.7] F11 Fullscreen editor border black / white