Irfanview has a nice thumbnail viewer with easy options for the thumbnail size. It is quick. It is on my desktop it must have installed itself at one of my installations. I don't use it very often. It is also available from within Irfanview. I view images, sort and organize in Lightroom and may do preliminary edits before exporting to a folder I have setup as a common directory between Gimp and Lightroom. Both programs default to this directory. If I want to process in Gimp I simply export a tif file because it is lossless (png not an option). The tif file shows up at the top of the open file listing in Gimp when sorted by date. It is quick and easy for me.
xcf not compatible with either Gimp nor Lightroom.
xcf not compatible with either Gimp nor Lightroom.