Yesterday, after reporting, I noticed that the 2305x1024 virtual resolution should be enough for setting 1280x1024. Today I tested again with the same laptop and projector and noticed that xorg.conf looks different:
I must have copied from the wrong xorg.conf backup. So now it's clear why the 1280x1024 resolution wasn't offered anymore. I'm attaching the complete xorg.conf file, just in case that helps.
Yesterday, after reporting, I noticed that the 2305x1024 virtual resolution should be enough for setting 1280x1024. Today I tested again with the same laptop and projector and noticed that xorg.conf looks different:
SubSection "Display"
Virtual 2640 768
EndSubSection
I must have copied from the wrong xorg.conf backup. So now it's clear why the 1280x1024 resolution wasn't offered anymore. I'm attaching the complete xorg.conf file, just in case that helps.