in the Vulkan examples, startNextFrame() is called internally. I'm calling my own render function when the decoder has a frame ready with m_window->frameReady() at the end (but no m_window->requestUpdate()) and get

QVulkanWindow: Attempted to call currentFramebuffer() without an active frame
QVulkanWindow: Attempted to call currentCommandBuffer() without an active frame

Is there an easy way to sync the vulkan renderer to an external decoder?