I am not able to install it in kibana 6.4.1

[1sunil1]

I am trying to install it in kibana-6.4.1.
with following command line: \kibana-6.4.1-windows-x86_64\bin> .\kibana-plugin install kibana-html-plugin-master

but i am getting this error:
Attempting to transfer from kibana-html-plugin-master.zip
Attempting to transfer from https://artifacts.elastic.co/downloads/kibana-plugins/kibana-html-plugin-master.zip/kibana-html-plugin-master.zip-6.4.1.zip
.\kibana-plugin : Plugin installation was unsuccessful due to error "No valid url specified."
At line:1 char:1

• .\kibana-plugin install kibana-html-plugin-master.zip
  • CategoryInfo : NotSpecified: (Plugin installa...url specified.":String) [], RemoteException
  • FullyQualifiedErrorId : NativeCommandError