Hi,
for me it’s show install.
https://i.ibb.co/GkCS3BN/xstoreinstall.png
when i tried to install. it shows failed
https://i.ibb.co/kmZxbh1/installedfailed.png
I’ve installed filemanager plugin, you can also upload the plugin from that.
just I checked that & found this.
https://www.awesomescreenshot.com/image/28129976?key=6c0d078c7fe0e0d27f862bc0604b7920