music

Yeah, that's not a valid notation I've come across in my music journey. I'd agree with you that it could be a placeholder symbol in that context, but I don't know why they wouldn't just restrict the pages instead. It could also be a unicode or file type issue like slatun mentions too, but overwhelmingly, unless you're working in a specific music softwares ecosystem and expect to be able to edit it, sheet music is just given as a pdf or image file and it shouldn't matter.