legend not working for bar plot with Plotly backend

[MarcSkovMadsen]

I would expect the legend attribute to also work for the Plotly backend in the example below. But it does not.

import hvplot.pandas  # noqa

from bokeh.sampledata.autompg import autompg_clean as df

table = df.groupby('yr').mean(numeric_only=True)
table.head()

table = df.groupby(['yr', 'origin']).mean(numeric_only=True)
table.head()

hvplot.extension("bokeh")
table.hvplot.bar(stacked=True, height=500, legend='bottom')

hvplot.extension("plotly")
table.hvplot.bar(stacked=True, height=500, legend='bottom')

HoloViews

I've tried to replicate this using HoloViews. But it seems the corresponding legend_position is only supported for the matplotlib and bokeh backends. There is an existing FR in HoloViews to support legend_position for the Plotly backend. See holoviz/holoviews#5221

It is possible to position the Plotly legend using a hook though.

import holoviews as hv  # noqa

hv.extension("plotly")

from bokeh.sampledata.autompg import autompg_clean as df

table = df.groupby(['yr', 'origin']).mean(numeric_only=True)

def hook(plot, element):
    # https://plotly.com/python/legend/#legend-positioning
    fig = plot.state
    fig["layout"]["legend"]=dict(
        yanchor="top",
        y=0.99,
        xanchor="left",
        x=0.01
    )

plot = hv.Bars(table, kdims=["yr", "origin"], vdims="mpg").opts(stacked=True, height=500, width=1000, hooks=[hook])

import panel as pn

pn.extension()

pn.panel(plot).servable()

Additional Context

I've been working on improving the bar docs. As a part of this I try changing the plotting backend. I would really, really like the documentation to work for all plotting backends. That is what I would expect as a user.