Contour not shown correctly in 3D Tri-Surf Plots

When plotting the 3D tri-surf figure, if we don't specify the facecolor of the plot, the contour will work well.
However, if we specify the faceolor of each faces, the contour will be stuck in the middle can't move and the coordinate
of each vertex also doesn't show its correct x,y,z.
The examples in the tutorials also have this problem.
Not sure if there have other way to specifiy the facecolor without making these issues.
Thank you very much for your help!

fig <- plot_ly(type = 'mesh3d',
  x = c(0, 1, 2, 0),
  y = c(0, 0, 1, 2),
  z = c(0, 2, 0, 1),
  i = c(0, 0, 0, 1),
  j = c(1, 2, 3, 2),
  k = c(2, 3, 1, 3),
  opacity = 0.5,
  contour = list(show = TRUE, color="#000", width=15)
  #facecolor = toRGB(viridisLite::viridis(4))
)
fig

fig <- plot_ly(type = 'mesh3d',
  x = c(0, 1, 2, 0),
  y = c(0, 0, 1, 2),
  z = c(0, 2, 0, 1),
  i = c(0, 0, 0, 1),
  j = c(1, 2, 3, 2),
  k = c(2, 3, 1, 3),
  opacity = 0.5,
  contour = list(show = TRUE, color="#000", width=15),
  facecolor = toRGB(viridisLite::viridis(4))
)
fig

Start by running the two provided R plot_ly mesh3d examples from the issue and compare contour movement and vertex coordinates with and without facecolor. Trace the 3D tri-surf rendering path to identify the difference, and consider the issue done when facecolor no longer causes incorrect contour positioning or coordinates.