title: Remove point outlines in scatter3d plot points
body: <p>I am working on a python dash app. I have created a 3d scatter plot based on a dataframe <code>df</code>. The points on the plot all have white outlines, and when they are clustered tightly, the outlines make it look messy. Is there a way to remove the outlines?</p>
  
  <pre><code>import plotly.plotly as py
  import plotly.graph_objs as go
  import pandas as pd
  
  df = pd.read_csv("./data.csv")
  
  data = [
      go.Scatter3d(
          x=df[x_axis],
          y=df[y_axis],
          z=df[z_axis],
          mode='markers',
          marker=dict(size=df['size_col']),
      )
  ]
  
  layout = go.Layout(
      scene=dict(xaxis={'title': 'x'},
                 yaxis={'title': 'y'},
                 zaxis={'title': 'z'}),
      margin={'l': 60, 'b': 40, 't': 10, 'r': 10},
      legend={'x': 0, 'y': 1},
      hovermode='closest'
  )
  
  fig = go.Figure(data=data, layout=layout)
  py.iplot(fig, filename='simple-3d-scatter')
  </code></pre>
  
  <p>This is what it currently looks like for me: <a href="https://i.stack.imgur.com/Sc6xb.jpg" rel="nofollow noreferrer">3d scatter plot</a></p>
  
  <p>It should be possible because when looking at <a href="https://plot.ly/python/3d-scatter-plots/#3d-scatter-plot-with-colorscaling" rel="nofollow noreferrer">https://plot.ly/python/3d-scatter-plots/#3d-scatter-plot-with-colorscaling</a>, the plot does not have these white outlines.</p>