Yeah, I've run into the same bug. Chrome and Firefox, there was no side scrolling. I had a tiny bit of luck in Edge, but then it died after the first level on me. Windows 11 here as well.
Hi guys, I uploaded a new build here which hopefully resolves the issue.
https://alphonsus.itch.io/gold-rush-1898-fixed
Please let me know if this one works now. Thanks so much again for showing interest to my entry!