Thanks for both your answer.
In fact, i would like to see this variable in the URL in order to access the site later via direct URL.
It’s not possible to duplicate each document in order to give them the desired aliases (way too long and not convienent).
I maybe have not well explained what i try to achieve, and, i think that it is not possible to do it with modx without hacking o bit.
Here is my configuration:
The welcome page is like below:
www.mysite.com
Containing a form allowing to select a brand.
Once validated it send the user to another page via GET:
www.mysite.com/fr/bienvenue.html?brand=choice
I really need to view the brand in the URL, and i would like to set the url like
www.mysite.com/fr/bienvenue-choice.html or www.mysite.com/fr/bienvenue-choice2.html for example.
In many tutorials they explain that it’s possible to catch the form submit and rewrite the url via the QUERY_STRING parameter.
I’ve been playing with the parameters but it doesn’t work wich seems to be a limitations of Modx (or most likely, a limitation of my coding skills

)