Colorbar LaTeX title renders improperly

I have posted this issue on plotly.py (here) however, someone on the plotly community forum said I should post it here as well.

I am trying to implement a LaTeX math title for my colorbar and plotly is having some trouble rendering it. I am using Python 2.7, Plotly 4.5.2. My code:

fig = go.Figure()
fig.add_trace(go.Scatter(x=x_data, 
                         y=y_data,
                         mode='markers',text=obj_name,name='',
                         marker=dict(symbol='circle',size=12,line=dict(width=1,color='SlateGray'),
                                     opacity=0.75,color=log_mbh,colorscale='Rainbow',showscale=True,
                                     cmin=6.0,cmax=8.0,
                                     colorbar=dict(title=dict(text=r'$\Large\alpha\beta\gamma\delta$',side='top'),
                                                   thickness=50,tickmode='array',tickvals=[6.0,6.5,7.0,7.5,8.0]), 
                                    ),
                         )
             )
fig.add_trace(go.Scatter(x=np.arange(0,300,10), y=np.arange(0,300,10),
                         line = dict(color='LightSlateGray', width=2, dash='dash')))

fig.update_layout(
    template='plotly_white',
    xaxis = dict(showgrid=False,ticks='inside',zeroline=True,zerolinecolor='black',rangemode='tozero'),
    yaxis = dict(showgrid=False,ticks='inside',zeroline=True,zerolinecolor='black',rangemode='tozero'),
    xaxis_title=dict(text=r'$x$'),
    yaxis_title=dict(text=r'$y$'),
    font=dict(size=16),
    showlegend = False,
    autosize   = False,
    width      = 750,
    height     = 750,
    margin     = dict(l=50,r=50,b=50,t=50,pad=10),
)

fig.show()

Which produces the output:

As you can see, the LaTeX title seems to be rotated 90 deg, and ignoring side='top'. I have tried to increase the width of the colorbar and increase the plot's margins to no avail. Is there a workaround or solution for this problem?

Update: I have found a workaround but not a solution. This is definitely a bug as far as I cant tell.

One option, if you do not require Greek alphabet, is to simply use HTML code, simply using italics, superscripts or subscripts.

If one wants to use Greek letters, HTML entities don't work, but a few decimal and hexadecimal codes do work.

This issue should be addressed, especially if Plotly is to be used for publishing purposes. Otherwise, Matplotlib is the alternative that does work.

首先复现所提供 Python 示例中的 colorbar 标题情况，重点关注 plotly.js 中 colorbar 标题的渲染。验证 LaTeX 文本如何处理 title side='top' 和旋转；当标题无需报告中的 workaround 即可按要求的方向和位置渲染时，即完成。