Static plotly in rmarkdown html

So, ggtern is broken and the package author may never fix the package, but plotly works beautifully to great ternary plots (which I’ve already done to make an interactive ternary).

Is there a way to make a plotly plot knittable to a pdf? I know there’s a static image export, but perhaps is there something just to plot the plot as a static image (e.g. like a standard plot() function in R)?