Upper Cross Syndrome Stretches for Better Posture

I have that typical gamer posture with the forward head and rounded shoulders. I am looking for upper cross syndrome stretches for better posture because it is starting to cause some tension headaches. I am in the UK and I spend most of my day at a desk which I know is the root of the problem.

I have started doing chin tucks and some doorway chest stretches. I am also trying to strengthen my mid back with some face pulls and rows. I have heard that stretching the levator scapulae and upper traps can also help with the neck tension. I am trying to be more mindful of how I sit but it is so easy to slouch when I am focused on work.

Does anyone have a quick five minute routine that I can do at my desk? I am looking for something that provides immediate relief and helps me stay more upright throughout the day. I would love to hear from others who have successfully corrected their upper cross syndrome!