我读了一些地方，你可以默认使用 apt 安装 Docky，但这不起作用。尝试添加存储库，但它是其中之一，因为它未经授权或其他原因而不会更新。是否有适用于 Docky 的 Ubuntu 19.04 的存储库？
编辑：@user535733
> $ sudo add-apt-repository ppa:docky-core/stable [sudo] password:
> This ppa is currently used for builds of release builds of
> docky and plank. More info:
> https://launchpad.net/~docky-core/+archive/ubuntu/stable Press [ENTER]
> to continue or Ctrl-c to cancel adding it.
>
> Ign:1 http://dl.google.com/linux/chrome/deb stable InRelease Hit:2
> http://archive.canonical.com/ubuntu cosmic InRelease
> Hit:3 http://us.archive.ubuntu.com/ubuntu disco InRelease
> Hit:4 http://dl.google.com/linux/chrome/deb stable Release
> Hit:5 http://us.archive.ubuntu.com/ubuntu cosmic InRelease
> Get:6 http://security.ubuntu.com/ubuntu disco-security InRelease [97.5
> kB] Hit:7 http://us.archive.ubuntu.com/ubuntu disco-updates
> InRelease Hit:8 http://us.archive.ubuntu.com/ubuntu
> cosmic-updates InRelease Ign:9
> http://ppa.launchpad.net/docky-core/stable/ubuntu disco InRelease
> Hit:11 http://us.archive.ubuntu.com/ubuntu disco-backports InRelease
> Err:12 http://ppa.launchpad.net/docky-core/stable/ubuntu disco Release
> 404 Not Found [IP: 91.189.95.83 80] Reading package lists... Done
> E: The repository 'http://ppa.launchpad.net/docky-core/stable/ubuntu
> disco Release' does not have a Release file. N: Updating from such a
> repository can't be done securely, and is therefore disabled by
> default. N: See apt-secure(8) manpage for repository creation and user
> configuration details.
您知道，只是您通常无法更新 repo 错误。