No option to add custom resolution

[koengabriels]

From other issues postes I see that there is an option to edit the available modes at the bottom of the list of available modes, this does not appear in the menu for me.

[tomiko23lol]

I have the same issue, I dont see EDIT option in resolution drop down menu.

I tryed to specify custom resolution over Terminal, but no luck so far.

I am geting Error: Could not select a new mode.

I am using this resolution with my Windows machine (using custom resolution in Nvidia drivers) on 4k 50" monitor and result is ultrawide with black bars on top and bottom, but I can not force MAC to do the same.

Could You help please?

PS: running on macOS Big Sur version 11.5.1, MacBook Pro 13-inch, M1, 2020, 16GB ram.
If You need more info please let me know.