Backports são
Backports do Kubuntu
link :
PPA description
Backports of new versions of KDE and major KDE apps for Kubuntu which are either too large a change or not yet tested enough to go to Ubuntu Backports.
Está disponível para o Lucid: qt4-x11 (4: 4.7.0-0ubuntu2 ~ lucid1 ~ ppa2).
Atualizando de um PPA
I'm running xubuntu and I really don't understand backports anyway.
Você pode acessar os Backports do Kubuntu e clicar em "Ler sobre a instalação": link . A atualização só atualizará os pacotes instalados (Qt).
Downgrade do PPA
Um pacote:
:~$ apt-cache show ppa-purge
Description: disables a PPA and reverts to official packages
This program disables a PPA from your Software Sources and reverts your system back to the official Ubuntu packages. You can use this to return your system to normal after testing a new version from a PPA.
Homepage: https://launchpad.net/ppa-purge
Ele está disponível nos back-back lucid: link
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