title: Second y axis vanishing on ggplotly command with dynamick ticks =true, ggplot2
body: <p>I have created the following dataframe and associated ggplot chart in R
  First we import the libraries using R</p>
  
  <pre><code> library(plotly)
   library(ggplot2)
  </code></pre>
  
  <p>Next we create the dataframe as follows</p>
  
  <pre><code>    dataframe_1&lt;-data.frame("Month"=c(1:12))
      dataframe_1$Sales&lt;-25*dataframe_1$Month
      dataframe_1$Fac1=dataframe_1$Sales/100
      dataframe_1$Month&lt;-as.character(dataframe_1$Month)
  </code></pre>
  
  <p>Next we create a ggplot based bar chart combined with a line chart as folllows</p>
  
  <pre><code>   p&lt;-ggplot(data = dataframe_1, mapping = aes(x = Month, y = Fac1))+geom_bar(data = dataframe_1, mapping = aes(x = Month, y = Sales/100, fill = "#82e600", text=paste0("Sales:", Sales)),stat="identity")+geom_line(mapping = aes(x = Month, y = Fac1, group = 1))+geom_point(mapping = aes(x = Month, y = Fac1, group = 1, text=paste0( "Factoid:", Fac1)),    inherit.aes = FALSE)+scale_y_continuous(sec.axis = sec_axis(~.*100, name = "Sales"))+labs(fill =  "Sales")
  </code></pre>
  
  <p>When we render the plot p, we get a plot with two y axes. However, when we render the dynamicticks as true, the second y axis disappears</p>
  
  <pre><code> ggplotly(p = p, tooltip = "text", dynamicTicks = TRUE)
  </code></pre>
  
  <p>I request someone to take a look and help.</p>