Save map with widget as video/html_video

I created a map with a widget. The widget looks as following:

time_slider = widgets.interactive(var_map_interactive, time_sel=widgets.IntSlider(description = "Time", min = 0, max = t_end, step = 5, readout_format = "d"), continous_update = True)

I now wanted to save this as a widget stream using the WidgetStream from ipywebrtc

view_stream = WidgetStream(widget=time_slider)

and then as a VideoRecorder

recorder = VideoRecorder(stream=view_stream)

However, eventhough the map with the widget works on its own in my Jupyter notebook, the "recorder" does not display anything. Any ideas why this is happening?

Also, how would I be able to create a html_video out from the recording?

Thanks for your help!