Hey, thanks for trying it out!
The version of the game engine (Godot) I am using is experimental, the deploy of the html5 is hit and miss: but there are lot of people working on it, I hope soon will be able to deploy html5 binary more consistently.
As for the mid-air facing, I've opted for something "inbetween" fixed position and turn around. Now the heroine will tilt her body backward when pressing the counter direction she's facing and will return on place once the counter-action is released. I think this is the best compromise between visual feedback for your action without break the visual consistency (instantly mirror the horizontal axis of the sprite)
