Wow. I have tried this out in my VM. At first glance it looks like this:
before:
the print was too dark
after:
the print has the same brightness as it had in windows
before:
dry-time in duplex-mode was always fix: about 2 seconds
after:
I guess 3+
I am fulfilled with happiness. It feels like Christmas. This way I can use this printer in Linux.
Thank you all. You did me a great service.
(Of course: I can still not change brightness, as I was also not able to change brightness in Windows. Because this printer does not support this setting. But it's not serious, as long as my prints are not too dark.)
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a) After the Install, I had to restart the VM with the printer connected and "on". And after I had the printer in "printer settings".
b) And there was no need for this change:
ipp-usb is not provided for buster. However, its author distributes a package that functions provided the device is exposed to the local network by editing /etc/ipp-usb/ipp-usb.conf and having
Source:
https://wiki.debian.org/CUPSDriverlessPrinting#summary