I had to cull through 1273 photos today (I shoot wildlife and today was particularly good ). Usually I end up with a few hundred photos in a single folder only and hadn’t noticed any issues before (I think the biggest folder before today had between 600 and 700 photos).
I have my filter set so that rejected images get filtered out, so that as soon as I reject them, they disappear from the image browser.
However, today there was a very noticeable delay between rejecting the image (by hitting 9) and the image disappearing from view. Sometimes 1 or 2 seconds, in at least one instance I even got the spinning rainbow mouse pointer.
I resorted to not filtering out the rejected images and instead do the tedious reject + cursor right method instead. While doing that, I also noticed that moving right at the end of a line (13 thumbnails in a line) to jump the first image of the next line also took longer than usual.
Anyways, maybe this could be improved in future versions.
PS: I consider this a performance bug of sorts, hence the bug tag.