I also refunded my Q90R. I spent a week fighting with support to try and get them to pass the issue over to the engineers to attempt to replicate but it was utterly futile. I'm not convinced support are even able to contact the engineering team. I genuinely have no idea how legitimate issues can progress through to firmware fixes if users can't get issues seen by the technical team. This is your flagship 4K TV, you'd think they'd be keen to handle reports of issues (I had multiple sets, all were identical). Awful. Absolutely awful.
Not my video, another owner's, but this shows it well.
I've made this video to show awareness of this issue. If you have the same issue on a Samsung Q90R, please leave a comment and contact Samsung to get the point across.*** Ghosting issue with the Samsung Q90R in Game Mode with 4K content. Does not happen during 1080p content. Brighter content will