Ensure Renderer.html works with comms msg_handler
@@ -276,6 +276,8 @@ class Renderer(Exporter):
html = tag.format(src=src, mime_type=mime_type, css=css)
if comm and plot.comm is not None:
comm, msg_handler = self.comms[self.mode]
+ if msg_handler is None:
+ return html
msg_handler = msg_handler.format(comm_id=plot.comm.id)
return comm.template.format(init_frame=html,
msg_handler=msg_handler,
