执行以下命令来安装缺失的字体:
wget https://raw.githubusercontent.com/powerline/powerline/develop/font/10-powerline-symbols.conf
wget https://raw.githubusercontent.com/powerline/powerline/develop/font/PowerlineSymbols.otf

sudo mkdir /usr/share/fonts/OTF

sudo cp 10-powerline-symbols.conf /usr/share/fonts/OTF/

sudo mv 10-powerline-symbols.conf /etc/fonts/conf.d/
sudo mv PowerlineSymbols.otf /usr/share/fonts/OTF/

然后重启终端,恢复正常