Left Sidebar Width and Right Sidebar Width values are forced to increase in increments of 5 and cannot be typed in manually. Please fix this so any number may be entered.
But it’s dissimilar to other parts of your interface. For example, the Mobile Menu Breakpoint slider goes in increments of 10, but you can edit the field manually. There is no reason you shouldn’t be consistent, and no reason to limit the sidebars in this way. What you mean by “works for most” is “not many people complain”. Those are not the same thing. I bet many people give up and accept the limitation.