Win32 WSI and SendMessage

> Some Vulkan functions may call the SendMessage system API when interacting with a VkSurfaceKHR through a VkSwapchainKHR. In a multithreaded environment, calling SendMessage from a thread that is not the thread associated with pCreateInfo::hwnd will block until the application has processed the window message. Thus, applications should either call these Vulkan functions on the message pump thread, or make sure their message pump is actively running. Failing to do so may result in deadlocks.

Is there an example of what win32 window message can be sent when calling vkCreateSwapchainKHR/vkQueuePresentKHR/vkAcquireNextImageKHR... and in what case?