Yep that was it!! Alright I actually played it this time! As others have said it's comfy as heck, I really enjoyed playing it.

Jumping on a croc's head repeatedly doesn't reset the "down" timer so it just kind of pops back up while you're jumping on it.

If you move onto a screen from blank space to where a block is you get stuck, like this:

And you have to jump to get out. You can hit the colored block switches while standing inside of the colored blocks to get stuck as well, and that one requires a restart to fix. Gave me a chance to play as Corel though.  Are there any differences? I can't seem to find any.

The coin pickup things look more like arrows than pickups. I was trying to figure out what they were pointing at (i'm probably just stupid)

The bomb timer seems kind of random? Sometimes it would just explode immediately and other times it would take quite a while. Also, this is a small thing, but I didn't expect it to pick up automatically so I kept hitting S and immediately dropping it like a dummy.

I think I already saw something about this but that far left area underground is a REALLY tight spot, took me several tries to get out.

Overall I think it's an achievement you did this in HTML5! I wouldn't even know where to begin. It's very charming and all of the mechanics are tight/responsive and fun to play with. Great work! I can't wait to play more!!