I know the solution is already given. But we’ve also had a case where we had to support 4K screens, and they expected more content on the 4K screen than on the regular screens.
Our solution was to simply develop each screen as a template. For the small screens, use those templates directly into a window. And for the big screen, show 4 of those templates.
Even if the application is already developed, it’s usually not that hard to copy-paste all content from a window to a template.