R plotly Update Title When Using Transform Filter

Question

I've created a graph that lets you pick which group's data to plot. I'd like to change the title when you pick the group, but I'm not sure how or if its possible. I'm having trouble learning which way to structure lists for certain plotly parameters. Even if I could add custom text to graph would probably work.

#Working Example so Far
library(plotly)

x <- c(1:100)
random_y <- rnorm(100, mean = 0)
random_y_prim <- rnorm(100, mean = 50)
mydata <- data.frame(x, random_y, random_y_prim, group = rep(letters[1:4], 25))

# Make Group List Button

groupList <- unique(mydata$group)

groupLoop <- list()
for (iter in 1:length(groupList)) {
  groupLoop[[iter]] <- list(method = "restyle",
                       args = list("transforms[0].value", groupList[iter]),
                       label = groupList[iter])
}


# Set up Axis labeling

f <- list(
  family = "Verdana",
  size = 18,
  color = "#7f7f7f"
)

xLab <- list(
  title = "x Axis",
  titlefont = f
)
yLab <- list(
  title = "y Axis",
  titlefont = f
)


fig <- plot_ly(mydata, x = ~x, y = ~random_y
               , type = 'scatter', mode = 'lines',
               transforms = list(
                 list(
                   type = 'filter',
                   target = ~mydata$group,
                   operation = '=',
                   value = groupList[1]
                 )
               )
)


fig <- fig %>% 
  layout(
  title = "Updating Practice",
  xaxis = xLab,
  yaxis = yLab,
  updatemenus = list(
    list(
      type = 'dropdown',xanchor = 'center',
      yanchor = "top",
      active = 1,
      buttons = groupLoop
    )
  )
)

fig