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I see there is a Youtube plugin for Qmmp "to search and play musics directly from YouTube ".
How should it be installed?
It is not a part of the Qmmp Plugin Pack (qmmp-plugin-pack).
The Youtube plugin for Qmmp project was updated. There, you can find all information about how to install the plugin.
If you are an ArchLinux user, you can install it directly from AUR with:
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