add demo.queue()

app.py

@@ -343,4 +343,5 @@ with gr.Blocks() as demo:
     vid_but.click(video_detection, inputs=[vid_in, vid_conf_sl_det, vid_conf_sl_clf, vid_fr, vid_enc], outputs=vid_out)
 
 if __name__ == "__main__":
+    demo.queue()
     demo.launch(share=True)