Summary: After enabling HDR, text now has red and blue borders and becomes fuzzy to read.
Could use some ideas here even if it's "Disable KDE HDR" When I got HDR to work on my primary monitor, text becomes incredibly fuzzy and difficult to read. I've set scaling to 100% to disable it and I've noticed words have a red or blue drop shadow almost like I'm looking through the old primitaive 3D Goggles.
Solution
This was resolved by changing the refresh rate in display configuration.