Bokeh layouts in Holoviews Chord

Hello and thanks for the latest release (and all the work that you have done).
I have a question regarding bokeh layout style in chord object in Holoviews:

Is there a way to “eliminate” the white border (outline_line_color), or changing color?

I followed instructions on the with theme object

from bokeh.themes.theme import Theme

theme = Theme(
'attrs' : {
    'Figure' : {
        'background_fill_color': '#2F2F2F',
        'border_fill_color': '#2F2F2F',
        'outline_line_color': '#444444',
    'Grid': {
        'grid_line_dash': [6, 4],
        'grid_line_alpha': .3,

    'Axis': {
        'major_label_text_color': 'white',
        'axis_label_text_color': 'white',
        'major_tick_line_color': 'white',
        'minor_tick_line_color': 'white',
        'axis_line_color': "white"
hv.renderer('bokeh').theme = theme

But it did not work! Hope there is right place to ask this question and that makes sense!

Thank you,