stray 'pre-main prep time: 0 ms' in console

[kmader]

For me it comes from using the export_svg function from https://github.com/rich-iannone/DiagrammeRsvg/blob/master/R/export_svg.R and it is printed at the $call( portion before the output

# Create the SVG file
  svg <- 
    ct$call("Viz",
            gv$x$diagram,
            "svg",
            gv$x$config$engine,
            gv$x$config$options)

  return(svg)

It appears to be the same issue as https://github.com/brion/ogv.js/issues/304

[jsta]

Simply wrapping this call with invisible() does not suppress this message from printing.