参考网址：Ubuntu Flathub 设置 | Flathub
2.1）Install Flatpak
To install Flatpak on Ubuntu 18.10 (Cosmic Cuttlefish) or later, simply run:
sudo apt install flatpak
With older Ubuntu versions, the official Flatpak PPA is the recommended way to install Flatpak. To install it, run the following in a terminal:
sudo add-apt-repository ppa:flatpak/stable sudo apt update sudo apt install flatpak
2.2）Install the Software Flatpak plugin
The Flatpak plugin for the Software app makes it possible to install apps without needing the command line. To install, run:
sudo apt install gnome-software-plugin-flatpak
Note: the Software app is distributed as a Snap since Ubuntu 20.04 and does not support graphical installation of Flatpak apps. Installing the Flatpak plugin will also install a deb version of Software and result in two Software apps being installed at the same time.
Add the Flathub repository
Flathub is the best place to get Flatpak apps. To enable it, run:
flatpak remote-add --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo
Restart
To complete setup, restart your system. Now all you have to do is install some apps!
3.再回到之前的“wechat”搜索页面，点击“安装”按钮。会自动下载一个文件com.tencent.WeChat.flatpakref. 双击举行安装即可。
