I think you forgot to put the web build on your itch.io? I have the option to download it, but that doesn't really make sense, because you already provided Windows downloadable. Make sure you have checked the "HTML build" option.
My apologies; there was a game-breaking bug causing the game to display incorrectly within the embedded window. We haven't figured out how to solve it yet, unfortunately, so I decided to make it download-only.