use hex color with transparency in the colors parameter

Hello Developer:

plot_ly(mtcars, 
        x = ~mpg,
        y = ~cyl,
        color = ~as.factor(cyl),
        colors = c("#3B4992A3","red","green"))

When I use a hex color with transparency in the colors parameter, it doesn't work, how can I fix it？

When I use as below, although the colors are correct, but the order is wrong.

plot_ly(mtcars, 
        x = ~mpg,
        y = ~cyl,
        color = ~as.factor(cyl),
        marker = list(
          color = c("#3B4992A3","red","green")))

Start by reproducing the provided plot_ly(mtcars, ...) example with the transparent hex color in the colors parameter, then compare it with the marker color example. Trace how colors are assigned to factor levels and verify that transparent hex colors are accepted while the intended color-to-level order is preserved. Done means the example renders the expected colors in the expected order.