[kaszanka]

This time it's sadly just another case of a web developer who thinks he knows better than you what browser you should use, it works fine with

  // ==UserScript==
  // @name     oasis.decart.ai Firefox fix
  // @version  1
  // @run-at   document-start
  // @match    https://oasis.decart.ai/*
  // ==/UserScript==
  
  unsafeWindow.chrome = 1;