I did hold SPACEBAR sadly :(
I just tried again to be sure.
Also, good job on the music, I really like it !
So sad... If you still want to experience it, I would recommend you press H to unlock all abilities so that you can double jump that ledge, and also it grants you dash by pressing Z.
Actually the music is taken from Octopath Traveler, if you are interested in JRPGs, give it a try! (fun fact: as a pixelated "2D" JRPG, it was made by UE4)