That's because "TV-Server" isn't a string used in the default skin. There is no good solution for translating texts from skins yet.Am I wrong or "TV-Server" string for the menu button isn't in the translation file (neither in UIStrings.fr.resx or transifex)?
In french "Serveur TV" or "Télevision" should be better.
Ok thanks! I did the modification directly into the menu.cshtml file of BlueShift skin and it's ok for me.