This is really cool. I'm a big enjoyer of difficult platforming, although one of the hardest parts is not being able to modify the awkward control scheme. It's still fun and worth it to learn it. I got to the snowman boss, and I'm not sure if there is anything after that. I don't think so.
I also noticed there are collectibles really high up above your head. I couldn't figure out if it was possible to get up there.
The main thing: I'm assuming that you developed this on a high resolution screen and you don't realize that it's not scaling down for people who have smaller screens (like 1080p max). So we have to carefully zoom in as far as we can and even then we only see portion of the screen.
Good obstacle design though.