I've discovered another workaround, it works like this:
- booting with default arguments (without 'nomodeset')
- if on lightdm login screen goes blank, then attaching working external monitor via miniHDMI->VGA adaptor makes screen on laptop visible again
I've discovered another workaround, it works like this:
- booting with default arguments (without 'nomodeset')
- if on lightdm login screen goes blank, then attaching working external monitor via miniHDMI->VGA adaptor makes screen on laptop visible again