Best Answer golok , 06 February 2013 - 11:04 AM
Thanks Danny for your help!
The culprits were indeed among plugins. The "Post Types Order" and "qTranslate" plugins are simply not compatible. Individually activated, the NavBar is present everywhere, but when both are activated the problem occurs and NavBar disappears on “special” pages…
Conclusion: I'll get rid of the "Post Types Order" plugin and re-order my stuff using creation dates or something like that.
Yet, as soon as I find the time, I'll post a ticket on both plugin's website.