How to install & activate a c-lightning plugin in lightningd? I recently stumbled across the https://github.com/lightningd/plugins github repo and wanted to install the autopilot plugin. But how can I install and activate the plugin which I downloaded from the website.
As explained on the simple funds overview plugin you just have to start lightningd with the plugin argument like this:

lightningd --plugin=/path/to/plugin/directory/plugin-file-name.py


of course plugins could also be written in other languages than python. 

You see this mechanism also in action in this video which explains who to write and run your own plugins. 

Also you can move the plugin to the clightning codebase to the plugindirectory (version at time of giving that answer). plugins which are stored there are automatically called and activated on lightningd startup if the file of the plugin is executable. 

You will also need c-lightning version bigger than 0.6 as plugins where not a thing before.