Thanks for all the nice comments, everyone! :)
jlun2: I don't know why those lines are there in BizHawk. They aren't there
on my Game Boy Color or in VBA. My guess is it's a problem with the gambatte core.
And yes, that's the only spot in Dutch Under where the platform boost works (and that was right where I needed it the most too, for the horizontal push it gives). The only other place I know about is the place I originally discovered it in Goo Lagoon, on a seemingly normal bubble platform:
If it's too hard to see that GIF, it's also the first trick in
this minor tricks video.
