You're using X11 rather than Wayland, right?
What command are you using for xrandr?
Nope, I'm using Wayland. I went through the steps in this guide: https://itslinuxfoss.com/set-custom-resolution-using-xrandr/?utm_content=cmp-true
Well the method looks correct, but xrandr doesn't support full wayland, AFAIK. It's really meant for X11.
I haven't looked into this myself, but perhaps there's a newer tool that can get the job done?
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Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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