I just found this glitch on chapter 4: You have to mash the dash button to the right while madeline is in the bubble. I don't know if this allows you to phase through solid objets too, though. If it does it may help with speedrunning. I'm running an older version of the game.

What version were you running?

1.1.3 You can actually dash back and drop down a little bit earlier.

yeah people used to do that in earlier runs but it’s been patched as far as i know