When I use FigureWidget in v6.0.0 and v6.0.1 in Jupyterhub, even a very simple figure takes about 10 seconds to appear. This is particularly frustrating because it's the default renderer, so for example I see this if I just enter

px.scatter(x=[1,2,3],y=[4,5,6])

and execute the cell. In v5.24.1 the graph appears in about 1 sec. I'm currently in Africa, using a Jupyterhub instance on AWS in us-west-2, so at first I thought the distance may have contributed but a user in Montreal ( @cardinalgeo ) accessing the same instance reports about the same delay. My workaround, in cases where I don't need FigureWidget capabilities, is to change the default renderer:

import plotly.io as pio
pio.renderers.default = 'notebook_connected'

Local Jupyterlab - run either directly in a terminal or via docker - shows no noticeable delay using FigureWidget.