Thumbnails for large image files not displaying in project bins if GPU enabled

[jhbradley610]

Premiere Pro v23.1.0 on Win 10 21H2

The images are large (4k x 4k ish), non transparent PNG files. Importing them into the project (via File Explorer, or the Media Browser) results in blank thumnail images, unless I set the Mercury Playback Engine to software only mode. Which is a non-starter; obviously I want to use GPU acceleration.

I have the current nVidia drivers installed (528.02) for my GeForce 1060.

This is not an issue in v22.6.3. I can load the same exact images there, on the same machine, with GPU acceleration enabled, and the thumbnails display perfectly fine.

Also, smaller images (1920x1080) work correctly in v23.

FWIW, it seems to be related to file size rather than image dimensions, possibly. I took one of the PNGs (3668x3668 18MB) and converted it to JPG in Photoshop (3668x3668 7MB). v23 correctly generated the thumbnail for the JPG.

I have a simple high res PNG (3840x3024 213KB) - that also produces a correct thumbnail in v23.