You can see all of that Flash Gordon content listed down below.
Flash Gordon 4K Blu-ray Special Features Details
Brand new 4K restoration by Studiocanal from the original camera negative approved by director Mike Hodges
4K (2160p) UHD Blu-ray presentation in Dolby Vision (HDR10 compatible)
Optional 5.1 and 2.0 stereo DTS-HD Master audio
Booklet featuring new writing on the film[...]