docs: public synchronized boolean unregisterObject(Object object) {
          int i = MiscUtil.indexOfInstance(registeredObjects, object);
          
          if (i > -1) {
              registeredObjects.remove(i);
              
              for (IRegisterEvent onRegister : onRegisterList) {
                  onRegister.unregisterObject(object);
              }
              
              if (object instanceof IRegisterEvent) {
                  onRegisterList.remove(object);
              }
              
              return true;
          }
          
          return false;
      }