Bug#883554: cups keeps breaking network printer with implicitclass:

[David Fries <David@Fries.net>]

Package: cups
Version: 2.2.1-8
Severity: important

Dear Maintainer,

It seems to be every day or so the /etc/cups/printers.conf DeviceURI is
modified to replace the version that works with a version that doesn't.
This is printing to a cups system on the local network.
Was working with the cups in Debian jessie.

It doesn't matter if I use a dnssd (auto detected), ipps, ipp, it gets
replaced by,
DeviceURI implicitclass:Canon_BJC-2100
and that doesn't allow it to print.  I've even gone so far as deleting
the printer, the detecting it through the ipp web configuration
interface and after a day or so it goes back to the implicitclass.

Any ideas?

-- System Information:
Debian Release: 9.1
  APT prefers stable
  APT policy: (500, 'stable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.9.0-4-amd64 (SMP w/2 CPU cores)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages cups depends on:
ii  cups-client            2.2.1-8
ii  cups-common            2.2.1-8
ii  cups-core-drivers      2.2.1-8
ii  cups-daemon            2.2.1-8
ii  cups-filters           1.11.6-3
ii  cups-ppdc              2.2.1-8
ii  cups-server-common     2.2.1-8
ii  debconf [debconf-2.0]  1.5.61
ii  ghostscript            9.20~dfsg-3.2+deb9u1
ii  libavahi-client3       0.6.32-2
ii  libavahi-common3       0.6.32-2
ii  libc-bin               2.24-11+deb9u1
ii  libc6                  2.24-11+deb9u1
ii  libcups2               2.2.1-8
ii  libcupscgi1            2.2.1-8
ii  libcupsimage2          2.2.1-8
ii  libcupsmime1           2.2.1-8
ii  libcupsppdc1           2.2.1-8
ii  libgcc1                1:6.3.0-18
ii  libstdc++6             6.3.0-18
ii  libusb-1.0-0           2:1.0.21-1
ii  poppler-utils          0.48.0-2
ii  procps                 2:3.3.12-3

Versions of packages cups recommends:
ii  avahi-daemon                     0.6.32-2
ii  colord                           1.3.3-2
ii  cups-filters [ghostscript-cups]  1.11.6-3
ii  printer-driver-gutenprint        5.2.11-1+b2

Versions of packages cups suggests:
ii  cups-bsd                                   2.2.1-8
pn  cups-pdf                                   <none>
ii  foomatic-db-compressed-ppds [foomatic-db]  20161201-1
ii  hplip                                      3.16.11+repack0-3
ii  printer-driver-hpcups                      3.16.11+repack0-3
ii  smbclient                                  2:4.5.12+dfsg-2+deb9u1
ii  udev                                       232-25+deb9u1

-- Configuration Files:
/etc/default/cups changed:


-- debconf information:
  cupsys/backend: lpd, socket, usb, snmp, dnssd
  cupsys/raw-print: true