The overworld border is pretty limited to edit, especially because it's a fixed tilemap in comparison to e.g. the status bar, especially the super version. Because of that, I made this patch which enables you to edit at least the top and bottom part.
For a list with (in)compatible patches and codes and, check out this thread.
Note for Erik: I wouldn't mind if you had fixed the error yourself.
Yeah I worded what I meant to say in a wrong manner lol. I meant more like, what would the ASM sections manager (Disco) say to me if I just fix people's issues in the submissions.
But it's good you fixed it quickly! \o/
This patch is super cool, and I definitely reccomend it to people that want easier customization for the border. I definitely could use this for my future projects.
(also featured in the meanwhile, but I'm not sure what the criteria for submission featuring is. I'll ask.)