User:Subfader/Original thumbs too large

I uploaded a 300px image (62,8 KB): File:Broken-rust-bike-bicycle.jpg

> The originally uploaded, untouched image is returned (62,8 KB)

This could be ~ 15 KB!

Just check the thumb after ImageMagick:

To demonstrate it, I embed it as 299px >>> 14,2 KB!

Originals should never be returned in the frontend as they were uploaded. All displayed images should pass the image converter with the user's sharpening and JPEG compression settings!

This doesn't only happen with thumb px >= original width but esp. in srcset where the wasted bandwidth hurts even more: On mobile devices :(

https://phabricator.wikimedia.org/T101015