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Firefox and IE not working with R Plotly via RMarkdown HTML document

I have built an HTML document using Rmarkdown via R studio .
2 of the visualizations are plotly 3d scatters.
Both of these use < 50 points.
They render in chrome fine but NOT at all in IE and they cause Firefox to crash.
Is this a known issue/bug?
Is there a way to fix it?

I am using IE 11, Firefox 43.01