My printer (Canon Pixma TS205) requires cnijfilter to be installed. As the installation of the vendor RPM is not possible on Silverblue, I have compiled it from source to /usr/local. It contains cups filters and an own backend.
When I try adding the Printer using the included PPD file, it complains that the filter (and probably the backend) cannot be found. They are located at /usr/local/lib/cups/ and cups seems to lookup in /usr/lib/cups/ only, which is not writable on Silverblue.
Is there a way to work around the issue, e.g. expanding the Filter and Backend Path for cups?