It means the button has 2 commands : left and right mouse click separated by |. Note: Tooltip on button may display as xxx | yyy. box is screenshots of my PotPlayer version can be seen here my skin has evolved since the first release of my PotPlayer in French () in 5, I would appreciate that users give me a feedback by participating to the above poll ) There are English and French version and foreign users can now easily translate this skin. I'm happy to announce that my skins will always be available to download here (). Don't forget to install provided fonts on your system (just google how to install fonts on Windows if you're a very noob) Install: Just copy the dsf files you want to test or use in the skins folder under potplayer installation directory. Direct link toward skins package is here () but the history post is gone.for now. Note: See this post () that explains why potplayer related topic are gone from doom9.