The issue has nothing to do with file size.
There's a (very minor) bug in the 8ch server code where it treats files named .jpeg different upon hover than .jpg or .png
If you hover over PB notables you'll see that files named .jpeg don't appear but files named .jpg do. (Both should appear).
.jpeg == .jpg it's just a naming difference, the file structure is identical.
Memefarmer uses a script to clean the memearchive files, convert over-large .png files to .jpg with a little compression, and rename .jpeg → .jpg
Also those technically inclined might want to check out TRIMAGE, an interesting app I've been using for a few weeks now to remove excess bytes (unnecessary color profiles etc.) from .png and .jpg files.
We are a graphics warehouse and ammo armory, so we are continually trying to raise our game to a higher level.
Trying to keep file sizes manageable for the archive, for the benefit of phonefags with limited storage, to help ensure good response time on the site for everyone.
o7