Previews not "sticking"

I’ve used NLP to convert several thousand frames. I’ve rendered out 1:1 previews and have the LR policy to never delete previews. But when I browse through the images in the library grid view I have to wait for the images to render again from neg to positive. Same thing when I double click or use the “f” shortcut for full frame. Always a delay while the NLP conversion comes up. Any way to fix this?

Hmm, I have not seen this problem before. It may be something unique to your setup or system (hopefully someone with more expertise in Lightroom can chime in).

One thing to check for would be making sure your setup and system are optimized for Lightroom Classic and that you have the most recent version. This may help:

https://helpx.adobe.com/lightroom-classic/kb/optimize-performance-lightroom.html