I've been having this issue/bug/problem for a couple of weeks now (can't exactly pinpoint when it started happening) and it's getting really annoying to work with. Can't find anything related so making a post.
Whenever I use the "2strip.look" preset in the Color Lookup adjustment layer, my PS starts to get periods of complete unresponsiveness (~10 seconds) whenever I do anything that changes the luminosity of the document (work with curves, levels etc). It is the only preset that does this and whenever I hide the layer, it stops. When I re-enable it, it comes back immediately. Only my Photoshop is affected, yet task manager doesn't show any usual activity. I'm really scratching my head on this one, and I haven't seen posts about other users having this issue. What could be causing it? I enjoy two-tone color splits in my post-process work quite a bit so I would be sad if I had to avoid using that preset altogether, but I'm open to a workaround solution using different adjustment layers to achieve the same result.