Default style

Hi Yann,
I assume you're talking about the 'Style Combo', where the default style is determined by the cursor's surrounding, namely the elements which the cursor anchoring on.

So define a style been recognized on paragraphs will mostly been displayed as the 'default' one, which could be achieved by the following steps:

1. Define a custom styleset file at the path stylescombo/styles/custom.js with the following content:

CKEDITOR.addStylesSet( 'custom',
[
   // Define paragraph as the default style.
   { name : 'Default'      , element : 'p' }

   // Your other styles defined below.
   //...
]);