Content of a textarea field rendered in object edition

I have a class with 2 properties : a textarea (named "section") and a string (named "normerelated")
The textarea is the first in the properties list.

I have an object of this class with, in the textarea field, this content :

[[image:awww.jpg||style="width: 235px; height: 328px;"]]

When i'm in object edition the content is rendered and i can see the image.
See my attached screenshot.