Whenever I open my website in the desktop, in full window, I get a blank collum to the right, and a horizontal scrollbar.
I've checked, and there is nothing outside the design that would cause this.
All the breakpoints seem to be working.
This doesn't happen when on mobile.
Oh, and I also have an image filling the browser, but I still get this white collum to the right.
No thought, until you don’t give us a working link. Publish your site for free and temporarily to Businesscatalyst, using the „Publish“ button top right of Muse’s application window.
Try to solve your issues by following these advices: https://forums.adobe.com/thread/2434082