Sankey labels appear at strange locations

In vertical sankeys, mouseover labels of flows appear at strange locations, some of them outside the drawing area.

See here:

library(plotly)
library(rjson)

json_file <- "https://raw.githubusercontent.com/plotly/plotly.js/master/test/image/mocks/sankey_energy.json"
json_data <- fromJSON(paste(readLines(json_file), collapse=""))

p <- plot_ly(
  type = "sankey",
  domain = list(
    x =  c(0,1),
    y =  c(0,1)
  ),
  orientation = "v", # this is the only change to the original example
  valueformat = ".0f",
  valuesuffix = "TWh",
  
  node = list(
    label = json_data$data[[1]]$node$label,
    color = json_data$data[[1]]$node$color,
    pad = 15,
    thickness = 15,
    line = list(
      color = "black",
      width = 0.5
    )
  ),
  
  link = list(
    source = json_data$data[[1]]$link$source,
    target = json_data$data[[1]]$link$target,
    value =  json_data$data[[1]]$link$value,
    label =  json_data$data[[1]]$link$label
  )
) %>% 
  layout(
    title = "Energy forecast for 2050<br>Source: Department of Energy & Climate Change, Tom Counsell via <a href='https://bost.ocks.org/mike/sankey/'>Mike Bostock</a>",
    font = list(
      size = 10
    ),
    xaxis = list(showgrid = F, zeroline = F),
    yaxis = list(showgrid = F, zeroline = F)
  )

Result:

This is the mouseover of the flow currently shaded in dark grey. In general, labels of flows to the left of the plot appear at rather correct locations and labels of flows to the right of the plot are off or do not display at all.

> version
               _                           
platform       x86_64-w64-mingw32          
arch           x86_64                      
os             mingw32                     
system         x86_64, mingw32             
status                                     
major          3                           
minor          6.1                         
year           2019                        
month          07                          
day            05                          
svn rev        76782                       
language       R                           
version.string R version 3.6.1 (2019-07-05)
nickname       Action of the Toes      

> packageVersion("plotly")
[1] ‘4.9.1’

Comienza ejecutando el ejemplo de Sankey de R plot_ly proporcionado con orientación vertical y compara las etiquetas de hover en toda el área de dibujo. Sigue el punto de entrada del posicionamiento de las etiquetas de hover del flujo de Sankey y verifica que las etiquetas sigan alineadas con sus flujos, incluidos los enlaces de la derecha; añade o ejecuta una comprobación de regresión si se encuentra la ubicación de prueba relevante.