Thanks. I couldn't get the permanent item hack to work. I tried copy-pasting it into my code, tried using the patch editor on Bitsy Savior, and tried using Borksy (which just corrupts my game, it can't handle Bitsy Color, and also it gives me an error about "object destroyed" when I try to run it in Bitsy Savior without my Bitsy Color game data injected). I'll keep trying...
Yeah, unfortunately the hacks can be version dependent, which also means they don't work for all forks. In the future, you may want to specify when you are asking for solution for a fork since the version numbers aren't always the same as the current vanilla Bitsy.
But it sounds like Valeriy's suggestion should be pretty easy to implement, I hope it works for you!