Wolf21

Hi there ! Good News !

I found the error, thanks to macguru advising me the chrome developer tools.
Here’s a screenshot of the source code : http://image.noelshack.com/fichiers/2013/07/1360842258-blogerror.png
Actually it is a problem with the French translation using the single quote (while in the source, single quote and double quote are well dissociated). I switched my WP language to English and now it works fine.

In catablog-fr_FR.po file,
line 1570

#: ../templates/admin-library.php:283
msgid "Please select at least one catalog item first."
msgstr "Veuillez tout d'abord sélectionner au moins un objet dans le catalogue."

I tried to fix this on my website but the French language doesn’t update with my change. So I left the English version for the moment.