PlotlyJS: Feature of legendgroup disable the feature to toggle visibility of individual traces

General Usage
1

If you have to diagrams in one figure you can group the legend according to the related sub-plots by means of the feature legendgroup. Unfortunately, this breaks in my example below the interactive functionality to toggle visibility of individual traces, has someone an idea how to fix this?

using PlotlyJS

function _legend_groups()
    # ---
    # --- create object containing sub-plots():
    _fig_obj = PlotlyJS.make_subplots(
        rows = 1, cols = 2,
    #           column 1    column 2
        specs = [ Spec()    Spec()], # raw 1
        )
    # --- read vector of standard colors "colorway":
    _colorway = PlotlyJS.PlotlyBase._get_colorway(_fig_obj.plot) # we must take the field ".plot"
    # ---
    _fig_layout = PlotlyJS.Layout(;
        title_text       = "Legend Groups",
        xaxis_title_text = "time / s",
        yaxis_title_text = "Amplitude",
        yaxis_range      = [0, 4],
        yaxis2 = PlotlyJS.attr(
            title       = "Amplitude",
            overlaying  = "y",
            side        = "left",
            range       = [0, 4],
            scaleanchor = "y",
            scaleratio  = 1,
        ),
        xaxis2_title_text = "time / s",
    )
    # ---
    for i_segment = 1 : 3
        if i_segment == 1
            PlotlyJS.add_trace!(_fig_obj, PlotlyJS.scatter(; y = i_segment .* ones(4), 
                line_color = _colorway[i_segment], 
                legendgroup = "group1", legendgrouptitle_text="First Group Title", ), row = 1, col =1)            
            PlotlyJS.add_trace!(_fig_obj, PlotlyJS.scatter(; y = 1.1 * i_segment .* ones(4), 
                line_color = _colorway[i_segment], 
                legendgroup = "group2", legendgrouptitle_text="Second Group Title", ), row = 1, col =2)            
        else
            PlotlyJS.add_trace!(_fig_obj, PlotlyJS.scatter(; y = i_segment .* ones(4), 
                line_color = _colorway[i_segment], legendgroup = "group1", ), row = 1, col =1)            
            PlotlyJS.add_trace!(_fig_obj, PlotlyJS.scatter(; y = 0.5 * i_segment .* ones(4), 
                line_color = _colorway[i_segment], legendgroup = "group2", ), row = 1, col = 2)
        end
    end
    # ---        
    PlotlyJS.relayout!(_fig_obj.plot, _fig_layout) # only re-layout the field ".plot"
    return _fig_obj
end

display(_legend_groups().plot)