hello forum
I bring you this program that meets the requirements to execute the change of screen resolution graphically and easily using xrandr
This program creates a script and adds a line inside .xinitrc that allows each login to activate the script avoiding the hassle of manually executing the script in each session.
SOMETHING VERY IMPORTANT!!!
You must be SURE that the selected resolution is supported by the main monitor / screen
At the moment I have only tested this program on my cpu and its main monitor, I have not performed tests on external or extended screens so in this second case it may not work correctly
The external screen and / or extended screen options I'm still working on it
This program was tested on puppy (fossapup64 9.5, Devuanpup 9.6.0, Quickpup 20.0. #, Xenialpup 7.5, Groovypup64 and Precisely 5.8) and it worked without any problem.
I leave you this image of what you will see in this process
Cheers!!