We found the same problem on Ubuntu 16.04.5LTS recently.
In order to solve this problem, we tried to upgrade the system-config-printer package which installed on the system from [system-config-printer 1.5.7] to [system-config-printer 1.5.9+20170825-0ubuntu1] which has solved this problem, but it failed.
Could you tell me whether Ubuntu 16.04.5LTS only support system-config-printer 1.5.7, so we can't upgrade to system-config-printer 1.5.9+20170825-0ubuntu1?
We found the same problem on Ubuntu 16.04.5LTS recently.
In order to solve this problem, we tried to upgrade the system- config- printer package which installed on the system from [system- config- printer 1.5.7] to [system- config- printer 1.5.9+20170825- 0ubuntu1] which has solved this problem, but it failed.
Could you tell me whether Ubuntu 16.04.5LTS only support system- config- printer 1.5.7, so we can't upgrade to system- config- printer 1.5.9+20170825- 0ubuntu1?