Missing colors in heatmap if values are the identical

Hello!
when creating a heatmap where values are all the same on a continuous scale, I get the expected colors from ggplot. However, when I put my ggplot into ggplotly, the colors are gone and it's all gray. Only happends, when values are identical. Happens with version 4.9.3 of plotly.

library(ggplot2)
library(dplyr)
library(plotly)

data <- tibble(hour = c(1, 1, 2, 2), day = c(1, 2, 1, 2), evaluation = c(1, 1, 1, 1))
g <- ggplot(data = data, mapping = aes(x = hour, y = day))
g <- g + geom_tile(aes(fill = evaluation), color = "white")
g <- g + scale_fill_gradientn(limits = c(0, 1), colours = c("red", "green"), name = "Availability")

print(g)         # ok, all colors are green as expected
print(ggplotly(g)) # not ok, colors in heatmap are gray, expected to be green

Please let me know if you need more explanation or additional information to track this down.

Thank you and kind regards,
Heiko

从 issue 中可复现的 R 示例开始，跟踪评估值完全相同的连续热力图的 ggplotly 转换过程。比较 ggplot 和 ggplotly 的输出，然后验证转换后的图块使用了预期的绿色，而不是灰色。