Damn near 100%, yes

https://caniuse.com/?search=canvas

Yeah, I bet it would be trivial for one of their engineers to whip up a universally compatible, hardware accelerated image file converter in JS, using no external dependencies, and less than 50 lines of code. Hint: it uses Canvas

This is probably a clever way of doing native JPEG image conversion on the front end, instead of pulling in (or reimplementing) a universal image conversion library