lexicon and language switch snippet

I wrote a small snippet to set a specific cultureKey to force Lexicon to output the right language :




But.. when I put it in a page, and check with console.log the current modx cultureKey, it doesn't switch and always shows the context cultureKey (en).

In my mind the cultureKey allow to say to the Lexicon what language to output without to have to define language for each Lexicon placeholder (i.e. ...&language=`en`) but my snippet doesn't override the context setting cultureKey... why?