Someone on askubuntu.com recommended I start the preference file with a CR (start preference description on the 2nd line in the file), include a trailing CR (empty line at end of file) and be very particular to not include any extra space characters after any of the attributes. This appears to have worked.
I have not seen this documented anywhere, or what it relates to, but it might be something that could be clarified with an update in documentation. Thanks for your consideration. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to apt in Ubuntu. https://bugs.launchpad.net/bugs/1901053 Title: apt preferences files do nothing re: apt-cache policy Status in apt package in Ubuntu: Expired Bug description: apt-cache policy does not reflect priority set in /etc/apt/preferences.d/* avery@ChubbyChipmunk:/etc/apt/preferences.d$ apt-cache policy Package files: 100 /var/lib/dpkg/status release a=now 500 http://ppa.launchpad.net/webupd8team/y-ppa-manager/ubuntu focal/main amd64 Packages release v=20.04,o=LP-PPA-webupd8team-y-ppa-manager,a=focal,n=focal,l=Y PPA Manager,c=main,b=amd64 origin ppa.launchpad.net 500 http://ppa.launchpad.net/system76/pop/ubuntu groovy/main amd64 Packages release v=20.10,o=LP-PPA-system76-pop,a=groovy,n=groovy,l=Pop!_OS PPA,c=main,b=amd64 origin ppa.launchpad.net 500 https://packagecloud.io/slacktechnologies/slack/debian jessie/main amd64 Packages release v=1,o=packagecloud.io/slacktechnologies/slack,a=jessie,n=jessie,l=slack,c=main,b=amd64 origin packagecloud.io 500 http://apt.pop-os.org/proprietary groovy/main amd64 Packages release v=20.10,o=system76,a=groovy,n=groovy,l=System76,c=main,b=amd64 origin apt.pop-os.org 500 https://download.mono-project.com/repo/ubuntu stable-focal/main amd64 Packages release v=20.04,o=XamarinFocal,a=stable-focal,n=focal,l=Xamarin-Stable-Focal,c=main,b=amd64 origin download.mono-project.com 500 https://packages.microsoft.com/ubuntu/18.04/prod bionic/main amd64 Packages release o=microsoft-ubuntu-bionic-prod bionic,a=bionic,n=bionic,l=microsoft-ubuntu-bionic-prod bionic,c=main,b=amd64 origin packages.microsoft.com 500 http://ppa.launchpad.net/linuxuprising/shutter/ubuntu groovy/main amd64 Packages release v=20.10,o=LP-PPA-linuxuprising-shutter,a=groovy,n=groovy,l=Shutter screenshot tool and dependencies,c=main,b=amd64 origin ppa.launchpad.net 500 http://dl.google.com/linux/chrome/deb stable/main amd64 Packages release v=1.0,o=Google LLC,a=stable,n=stable,l=Google,c=main,b=amd64 origin dl.google.com 500 https://download.opensuse.org/repositories/devel:/kubic:/libcontainers:/stable/xUbuntu_20.04 Packages release o=obs://build.opensuse.org/devel:kubic:libcontainers:stable/xUbuntu_20.04,n=xUbuntu_20.04,l=devel:kubic:libcontainers:stable,c= origin download.opensuse.org 500 http://packages.microsoft.com/ubuntu/18.04/mssql-server-2019 bionic/main amd64 Packages release o=mssql-server-2019-bionic bionic,a=bionic,n=bionic,l=mssql-server-2019-bionic bionic,c=main,b=amd64 origin packages.microsoft.com 500 http://mirrors.vcea.wsu.edu/ubuntu groovy-proposed/main i386 Packages release v=20.10,o=Ubuntu,a=groovy-proposed,n=groovy,l=Ubuntu,c=main,b=i386 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy-proposed/main amd64 Packages release v=20.10,o=Ubuntu,a=groovy-proposed,n=groovy,l=Ubuntu,c=main,b=amd64 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy-proposed/multiverse i386 Packages release v=20.10,o=Ubuntu,a=groovy-proposed,n=groovy,l=Ubuntu,c=multiverse,b=i386 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy-proposed/multiverse amd64 Packages release v=20.10,o=Ubuntu,a=groovy-proposed,n=groovy,l=Ubuntu,c=multiverse,b=amd64 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy-proposed/restricted i386 Packages release v=20.10,o=Ubuntu,a=groovy-proposed,n=groovy,l=Ubuntu,c=restricted,b=i386 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy-proposed/restricted amd64 Packages release v=20.10,o=Ubuntu,a=groovy-proposed,n=groovy,l=Ubuntu,c=restricted,b=amd64 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy-proposed/universe i386 Packages release v=20.10,o=Ubuntu,a=groovy-proposed,n=groovy,l=Ubuntu,c=universe,b=i386 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy-proposed/universe amd64 Packages release v=20.10,o=Ubuntu,a=groovy-proposed,n=groovy,l=Ubuntu,c=universe,b=amd64 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy-security/universe i386 Packages release v=20.10,o=Ubuntu,a=groovy-security,n=groovy,l=Ubuntu,c=universe,b=i386 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy-security/universe amd64 Packages release v=20.10,o=Ubuntu,a=groovy-security,n=groovy,l=Ubuntu,c=universe,b=amd64 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy-security/main i386 Packages release v=20.10,o=Ubuntu,a=groovy-security,n=groovy,l=Ubuntu,c=main,b=i386 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy-security/main amd64 Packages release v=20.10,o=Ubuntu,a=groovy-security,n=groovy,l=Ubuntu,c=main,b=amd64 origin mirrors.vcea.wsu.edu 500 http://archive.canonical.com/ubuntu groovy/partner amd64 Packages release v=20.10,o=Canonical,a=groovy,n=groovy,l=Partner archive,c=partner,b=amd64 origin archive.canonical.com 500 http://mirrors.vcea.wsu.edu/ubuntu groovy/multiverse i386 Packages release v=20.10,o=Ubuntu,a=groovy,n=groovy,l=Ubuntu,c=multiverse,b=i386 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy/multiverse amd64 Packages release v=20.10,o=Ubuntu,a=groovy,n=groovy,l=Ubuntu,c=multiverse,b=amd64 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy/universe i386 Packages release v=20.10,o=Ubuntu,a=groovy,n=groovy,l=Ubuntu,c=universe,b=i386 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy/universe amd64 Packages release v=20.10,o=Ubuntu,a=groovy,n=groovy,l=Ubuntu,c=universe,b=amd64 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy/restricted i386 Packages release v=20.10,o=Ubuntu,a=groovy,n=groovy,l=Ubuntu,c=restricted,b=i386 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy/restricted amd64 Packages release v=20.10,o=Ubuntu,a=groovy,n=groovy,l=Ubuntu,c=restricted,b=amd64 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy/main i386 Packages release v=20.10,o=Ubuntu,a=groovy,n=groovy,l=Ubuntu,c=main,b=i386 origin mirrors.vcea.wsu.edu 500 http://mirrors.vcea.wsu.edu/ubuntu groovy/main amd64 Packages release v=20.10,o=Ubuntu,a=groovy,n=groovy,l=Ubuntu,c=main,b=amd64 origin mirrors.vcea.wsu.edu Pinned packages: $ apt-cache policy apt apt: Installed: 2.1.10 Candidate: 2.1.10 Version table: *** 2.1.10 500 500 http://mirrors.vcea.wsu.edu/ubuntu groovy/main amd64 Packages 100 /var/lib/dpkg/statu To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/1901053/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp