Can't add body field or other textfields in lightbox trigger

Hi,

First of all, sorry for my English which is very bad (you know i'm French :P, but i'm working on!).

I have a problem with lightbox trigger, i wan't to add my body field when lightbox open but it doesn't work.
I tried to add my replacement patterns in popup area and in caption area but nothing happen.

I've read some issues for this but they occured several years ago and i don't find my answer.

My project is a portfolio page with images.
On click, each image open a lightbox with full size image and details of the project so it's really important for me to can add a long text with my image.

Is it possible? and how?

Thanks in advance.