关于ubuntu更新源的事情

1.更新源
找到Software & Updates，将源更新为阿里云的源

在Other Software里将Canonical Partners勾上。

然后自己手动更新一下：

sudo apt update
sudo apt upgrade

** Canonical 合作伙伴软件仓库
The Canonical Partner repository offers some proprietary applications that don’t cost any money to use but are closed source. They include software like Adobe Flash Plugin. Software in this repository will appear in Ubuntu Software search results but won’t be installable until this repository is enabled.

要启用该库，请遵照上述步骤打开在软件和更新 中的其他软件标签页。如果您在列表中看到Canonical 合作伙伴仓库，请确保将其选中，然后关闭 软件和更新 窗口。如果没有看到该库，单击添加，然后输入：

deb http://archive.canonical.com/ubuntu cosmic partner

Click Add Source then close the Software & Updates window. Wait a moment for Ubuntu Software to download the repository information.