This morning I installed updates for Zorin and since that time the display is poor, fuzzy.
The graphics driver details:
vendor : NVIDIA Corporation
model : GM107M [GeForce GTX 860M]
driver : nvidia-driver-418-server - distro non-free
driver : nvidia-driver-440-server - distro non-free
driver : nvidia-driver-450 - third-party free recommended
That recommended driver is installed.
I tried different fonts but the rendering remains poor.
I have two questions:
how to repair the poor rendering
how to revert to a previous installation without making backups
I just noticed that the repository used has changed back to one that doesn’t allow updating:
The repository ‘http://us.archive.ubuntu.com/ubuntu artful-updates Release’ does not have a Release file.
N: Updating from such a repository can’t be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.