解决方法:
在终端执行如下几条命令:
sudo pkill杀死appstreamcli
wget - p/tmp https://launchpad.net/ubuntu/+档案/主/appstream_0.9.4-1ubuntu1_amd64.deb https://launchpad.net/ubuntu/+/+文件归档/主/+文件/libappstream3_0.9.4-1ubuntu1_amd64.deb
sudo dpkg - i/tmp/appstream_0.9.4-1ubuntu1_amd64.deb/tmp/libappstream3_0.9.4-1ubuntu1_amd64.deb 问题即可解决。
