As I said, then, the issue seems to be with the streaming apps, not with the panel. If the panel wasn’t producing true black and it was a simple setting issue, then the problem would happen universally, regardless of the source. If you’re seeing true black via one method (UHD via HDMI) and not another (the Netflix app), then the issue lies with the app, not with the panel. That said, it would appear that this is still LG’s issue to correct if they’re responsible for the built-in app (or is that a Netflix problem?). I suppose one way to verify this would be to see if the issue impacts Netflix via a *player* app (not LG’s built-in variety)?Your statement is not true for LG internal applications. Internal LG Netflix App doesn't sent the black bars info in the stream in Dolby Vision. Therefore, if the black is somehow rendered wrong in the stream, you will see it only on actual content and not on the letterbox black bars. I only use internal app and see tons of raised black errors across the available content.
However, the statement probably is true for external HDMI DV content, where letterbox are sent within the stream. I did quick test using Xbox One X Netflix app and could confirm I had consistent error on raised blacks during end credits and on the letterbox bars in the same time - they were essentially the same. Issue is far more worse on the Xbox One X and "contrast workaround" wasn't working here.