You can import easily to your chrome with
your-folder-path$ git clone https://github.com/valterbarros/button-pause-youtube.git
this will create a new folder in your-folder-name
and with this you can import in your chrome acessing ... -> more tools -> extensions
you will need enable Developer Mode and click in load unpacked extension...
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This will open a file manager and you have to find your-folder-path/button-pause-youtube-master and click in open to finish
Only one coriguration is necessary, set the shutcut to pause youtube video click in Keyboard Shortcuts
And set shortcut to pause youtube video I recommend ctrl+shift+p, select option global if you want pause youtube video from anywhere (even with chrome minimized).
To select which video you want take control:
