However... it looks like the application you're trying to expose is not
available.
Original error: dial tcp 127.0.0.1:8055: connectex: Aucune connexion n’a pu être établie car l’ordinateur cible l’a expressément refusée.
This request would normally end up with 502 status code.
If that's what you intended please restart the tunnel with
--disable-proxy-error-page option
to remove this page and get regular 502 error.