L'application créative cloud ne me propose pas la nouvelle mise à jour Lightroom Classic 15.4, donc impossible de la télécharger.

LrC 15.4 is not currently available as Adobe has withdrawn the software update until Adobe can fix a bug. So as of right now, you cannot download and install LrC 15.4 — maybe tomorrow or the next day or the day after that it will be available, who knows?