Also, side question, if you don't mind me asking, what code did you use to get your customized scrollbar. I'm using Twine as well to code a story but I can't figure it out even after looking it up.
oh lord, i'm super sorry i'm getting to this so late :( i don't use itch.io that often
to answer the first: the error should be fixed now, i'll double-check it anyway but i did a quick bug update a little while back :)
the second: the scrollbar actually came with the template i'm using! if you'd like, and have it, you can add me on discord and i'll dive into the code and find you the specific bit to send over?