If the supported resolution isn’t available on an ultrawide or super-ultrawide external display connected to your Mac with Apple M1 chip
If you connect an ultrawide or super-ultrawide monitor to your Mac with Apple M1 chip, some resolutions supported by your display may not be available.
Apple is aware of this issue and resolution is planned for a future macOS update.
To see the additional resolutions for your external display, choose Apple menu > System Preferences, click Displays, then press and hold the Option key while you click Scaled.
This document will be updated as more information becomes available.