Eu gostaria de rebaixar o GNOME porque o 3.20 no meu Ubuntu 16.04 é uma bagunça. Existem inúmeras fontes na Internet (incluindo askubuntu ) dizendo como fazer isso, e é sempre:
sudo ppa-purge ppa:gnome3-team/gnome3-staging
sudo ppa-purge ppa:gnome3-team/gnome3
(opcionalmente também sudo ppa-purge ppa:gnome3-team/gnome3-next )
No entanto, estou chegando a lugar nenhum com isso.
$ sudo ppa-purge ppa:gnome3-team/gnome3-staging :
Updating packages lists
W: GPG error: http://download.opensuse.org/repositories/home:/Horst3180/xUbuntu_16.04 Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 5A7D1D38BEB6D886
W: The repository 'http://download.opensuse.org/repositories/home:/Horst3180/xUbuntu_16.04 Release' is not signed.
W: The repository 'http://ppa.launchpad.net/cardapio-team/cardapio-ppa/ubuntu xenial Release' does not have a Release file.
W: The repository 'http://ppa.launchpad.net/cardapio-team/unstable/ubuntu xenial Release' does not have a Release file.
W: The repository 'http://ppa.launchpad.net/synapse-core/ppa/ubuntu xenial Release' does not have a Release file.
E: Failed to fetch http://ppa.launchpad.net/cardapio-team/cardapio-ppa/ubuntu/dists/xenial/main/binary-amd64/Packages 404 Not Found
E: Failed to fetch http://ppa.launchpad.net/cardapio-team/unstable/ubuntu/dists/xenial/main/binary-amd64/Packages 404 Not Found
E: Failed to fetch http://ppa.launchpad.net/synapse-core/ppa/ubuntu/dists/xenial/main/binary-amd64/Packages 404 Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
Warning: apt-get update failed for some reason
$ sudo ppa-purge ppa:gnome3-team/gnome3 :
Updating packages lists
W: The repository 'http://ppa.launchpad.net/cardapio-team/cardapio-ppa/ubuntu xenial Release' does not have a Release file.
W: The repository 'http://ppa.launchpad.net/cardapio-team/unstable/ubuntu xenial Release' does not have a Release file.
W: The repository 'http://ppa.launchpad.net/synapse-core/ppa/ubuntu xenial Release' does not have a Release file.
W: GPG error: http://download.opensuse.org/repositories/home:/Horst3180/xUbuntu_16.04 Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 5A7D1D38BEB6D886
W: The repository 'http://download.opensuse.org/repositories/home:/Horst3180/xUbuntu_16.04 Release' is not signed.
E: Failed to fetch http://ppa.launchpad.net/cardapio-team/cardapio-ppa/ubuntu/dists/xenial/main/binary-amd64/Packages 404 Not Found
E: Failed to fetch http://ppa.launchpad.net/cardapio-team/unstable/ubuntu/dists/xenial/main/binary-amd64/Packages 404 Not Found
E: Failed to fetch http://ppa.launchpad.net/synapse-core/ppa/ubuntu/dists/xenial/main/binary-amd64/Packages 404 Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
Warning: apt-get update failed for some reason
O GNOME permanece a mesma versão após a reinicialização. Com licença, se isso é apenas uma questão de pesquisar alguma parte da saída, tentei procurar também algo geral relativo a ppa-purge failing. Eu sou um usuário final abaixo da média. Ficarei feliz em fornecer mais informações.
Conforme solicitado, $ sudo apt-get update output e $ sudo apt-get upgrade output:
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.