Hello, so i tried to put your script in my project and... It WoRkS :D Yeaaaah, Thanks !
I keep the "old" display on the background to verify that it's the same things at the same moment, and i add a script to be sure that the scrollcontenaire show always the "last text" entered, and stay "at the bottom" x) and it works to.
Only things to fix, when a text put in the label has more than 1 line, the bubble don't resize with it.

So, i think about a solution but i don't know, maybe if i count the number of the lines of the label, i can update the size of the bubble?
maybe a script like that? :
if label.number_of_the_line == 1:
panel.height = 32
if label.number_of_the_line == 2:
panel.height = 64
if label.number_of_the_line == 3:
panel.height = 96
or something like that...
(i choose "Autowrap" in the label's property, to be sure that the text displayed on a lot of line, and not one only)
I will see it this weekend, quietly x)...