Empty facets when using subplot on multiple facet plots with shareX = TRUE

When running the code below, the first subplot produces 4 empty facets in the two plotlys while the latter produces no empty facets (expected). I notice that the third and fourth xaxis x3 and x4 do not exist in the plotly object xaxis property in $x$data. It seems to be hard capped at two such that the traces intended for the >2 facets are accumulated into the second facet (x2)

library(tidyverse)
library(plotly)
facet_plot <- ggplotly(
  tibble(x = rnorm(75), y = rnorm(75), type = rep(LETTERS[1:3], 25)) %>%
    ggplot(aes(x, y)) + geom_point() + facet_wrap(~ type))
subplot(facet_plot, facet_plot, nrows = 2, shareX = TRUE)
subplot(facet_plot, facet_plot, nrows = 2)

Comienza ejecutando el ejemplo reproducible de R con dos gráficos facetados y compara los resultados de los subgráficos con X compartido y X no compartido. Inspecciona las entradas xaxis del objeto x$data del gráfico, especialmente x3 y x4; se considera terminado cuando los subgráficos compartidos conservan todos los ejes de las facetas y no aparecen facetas vacías.