This games primary mechanic is that you can only jump when falling. So it's either you didn't pick up on that orrr there's some odd browser/html-related issue. If it's the latter then, yeah it works fine for me so I really have no clue where I'd start to figure out what the issue could be (sorry).

thank you!! we are aware of the frame drops and looking into fixing them asap.

UPDATE: frame drops have been significantly reduced now!!

ty!!