Pidgin themes, Pidgin smilies, Pidgin sounds
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Use players at the left side to listen the theme sounds.
To install the "skype sounds" sounds set, you should download it using the link below, unzip files and place it into themes folder. That folder's location depends on OS you use.
%appdata%\.purple\themes
Extract the content of the downloaded file into the "~/.purple/themes" folder and select new sound theme in the Pidgin preferences.
Note: "~" is your "home" directory in Linux, i.e. /home/username. To see the ".purple" folder in there, you might need to enable "Show hidden files" option in your preferred file manager.