It seems that WordPress MU Domain Mapping is incompatible with Visual composer.
The context :
- Wordpress 4.1
- WordPress MU Domain Mapping Version 0.5.5.1
- WPBakery Visual Composer Version 4.3.5 (I've just bought it to obtain the last version)
- Medicenter Theme (Latest Version: 22.12.2014 – v6.4)
The last screenshop from the chome developper tools : http://i.imgur.com/XOuHYHp.png
Thanks for your support.
David