High memory use when loading a folder with a lot of images - thumbnail view

Have a folder with a -lot- of screenshots: folder properties 15K files 154 folders 9GB.
That folder should urgently be reorganized, I know.
Started off doing so but things got terribly slow and Opus memory usage ended up at roughly 5GB (?) Things go terribly slow.

Thumbnail view is more or less a must, so I know what the files are about and properly name them before moving to sub folders.

No idea about the cause, but is there a solution for this?

Thanks.

Thumbnails are loaded into memory, there's not really any way around that.

You can reduce the maximum thumbnail size, which makes them take up less memory. Or reduce the number of files.

If it helps, you can also configure Opus only load thumbnails as they become visible, without loading the whole folder. (Of course, they will still require memory once they are scrolled into view the first time.)

The max thumbnail size setting Jon mentions is the main thing though.

Thanks a lot Jon and Leo !
(Yes, I really need to set me to clean up the mess...)