In fact, I didn't notice that since LyX 1.6, the main configuration file is located in .config/LyX. Deleting it fixed my issue. With no reason, "visibility" parameters of some GUI objects got "0" value, e.g.: 0\functions\visibility=0 instead of: 0\functions\visibility=10 -- Renaud Lacour <renaud at home-dn.net>