I believe this has been talked about previously: https://resource.dopus.com/t/scaling-up-tiny-images-in-thumbnail-view/9630 See the 4th post starting from 2016.
I was wondering if it would be possible to upscale folder thumbnails generated by Opus to fit when in Thumbnail View. Currently Opus downscales images that are too large, which works well.
However, I am having to manually upscale many smaller images in GIMP over and over again. It would be great if Opus could resize these images to fit on the fly.