Adding text shrinks bar chart area

Adding text shrinks the bar chart area. Below we render a bar chart where the bars are on the x-axis. The add_text() call actually vertically shrinks the area of the plot, such that the distance from the bottom bar to the x-axis "0" is increased. If you run this output without the add_text() call, you'll see that the vertical width of the bar charts increases.

Adding text should not have an effect on the bar chart.

# Shrunken plot area
require(plotly)
#> Loading required package: plotly
#> Loading required package: ggplot2
#> 
#> Attaching package: 'plotly'
#> The following object is masked from 'package:ggplot2':
#> 
#>     last_plot
#> The following object is masked from 'package:stats':
#> 
#>     filter
#> The following object is masked from 'package:graphics':
#> 
#>     layout

cats = c(letters, paste0(letters,'2'), paste0(letters,'3'), paste0(letters,'4') )

data = data.frame(
  y_axis_cat = rep(cats,8),
  x_axis_num = rep(5,length(cats)*8),
  cat = rep(paste0('Cat ',1:8), length(cats))
)

p = plotly::plot_ly(data) %>%
  plotly::add_bars(
    x = ~x_axis_num,
    y = ~y_axis_cat,
    color=~cat
  ) %>%
  plotly::add_text(
    x = 40,
    y = ~y_axis_cat,
    text = '40'
  ) 

^{Created on 2023-04-10 with reprex v2.0.2}

提供された R reprex を plotly::plot_ly()、add_bars()、add_text() とともに実行し、add_text() なしのバージョンと比較します。棒グラフの垂直方向の領域が縮小する原因となっているプロットレイアウトの挙動を追跡します。完了条件は、テキストを追加しても下側の棒と x 軸のゼロとの距離が増えなくなることです。