zoom out or larger screens: incompatible expansion

Previously, when I had canvas on a larger monitor than my laptop screen, Bettercanvas allowed the stretch of interfaces (including embedded sources for lectures, and all buttons for courses and within the courses themselves as well)—so that the dimensions would match a larger, more zoomed out screen. However, now everything is pushed to the side and to the left, and is therefore much smaller and very incompatible with uses of larger monitors, or any time I zoom out on chrome on my regular sized laptop. Please fix this back to normal!

screenshots show the large empty right hand side, which previously would stretch and accommodate all buttons and cards

ignore the white box, just covering details related to my course.