plotly heatmap traces rendered as line plots in Rshiny

plotly::plotlyOutput renders heatmap traces as line plots in a Rshiny dashboard.

I display two independent plotly charts, generated using plotly::renderPlotly, side by side on the same page (scatter traces on the left and heatmap traces on the right) in an Rshiny app.

When the chart is rendered for the first time, they appear as they should -- the heatmaps are shown as a heatmaps. When I alter the data plotted using some gui controls the heatmap is rendered as a line plot and never goes back to a heatmap.

The interesting thing is when the heatmap is displayed alone (without the scatter plot anywhere in the app) it behaves as expected and renders the correct charts.

The attached zip file contains a reproducible example that illustrates this error.

Steps to reproduce the error/bug:

1) Run the app and wait for the plots to load.
2) Click on the blue dropdown button in the bottom and add/remove one of the parameters (eg. DOSE).
3) Wait for the plot to load, and now you will see the heatmap converted to a line plot.

Any help in this regard will be greatly appreciated.

Best
Ram

scatter_heatmap_plotly.zip

Run the attached scatter_heatmap_plotly.zip reproducible example and follow the update steps with both charts present. Start with the plotly::renderPlotly and plotly::plotlyOutput paths involved in the R Shiny update, then verify that changing the dropdown leaves the heatmap rendered as a heatmap rather than a line plot.