Splom fig not showing any markers

Hello,
The sample code for the splom is not showing the scatter markers for me. I get all the different frames but no markers.

Has this issue been raised by anyone?

library(plotly)
library(dplyr)
df <- read.csv('https://raw.githubusercontent.com/plotly/datasets/master/iris-data.csv')
pl_colorscale=list(c(0.0, '#19d3f3'),
                   c(0.333, '#19d3f3'),
                   c(0.333, '#e763fa'),
                   c(0.666, '#e763fa'),
                   c(0.666, '#636efa'),
                   c(1, '#636efa'))
axis = list(showline=FALSE,
            zeroline=FALSE,
            gridcolor='#ffff',
            ticklen=4)

df %>%
    plot_ly() %>%
    add_trace(
        type = 'splom',
        dimensions = list(
            list(label='sepal length', values=~sepal.length),
            list(label='sepal width', values=~sepal.width),
            list(label='petal length', values=~petal.length),
            list(label='petal width', values=~petal.width)
        ),
        text=~class,
        marker = list(
            color = as.integer(df$class),
            colorscale = pl_colorscale,
            size = 7,
            line = list(
                width = 1,
                color = 'rgb(230,230,230)'
            )
        )
    ) 

Start by running the supplied R sample for the plotly.R splom trace and inspect how the frames and scatter markers are rendered. The issue is resolved when the sample displays the expected markers across the splom frames.