Handling missing rows and NAs with animated chart

Hi.
I found out that when using animated plotly chart you need to have the same number of observations for each of your factors. Meaning -> one missing observation results in whole trace being discarded for entire duration of the animated chart. That is especially a problem when you use time-series data and some of your traces start later, and/or end sooner than others. In addition even when I manually recreate the missing row with NAs, the trace containing these NAs cannot be graphed. Is there any workaround beside of imputing null values for the missings? Thanks!

Example:

library(gapminder)
library(plotly)
library(dplyr)

#working example with no missings
gapminder %>% 
  group_by(year, continent) %>% 
  summarise(pop = mean(pop), gdpPercap = mean(gdpPercap), lifeExp = mean(lifeExp)) %>%
  plot_ly( x = ~gdpPercap, 
           y = ~lifeExp, 
           size = ~pop, 
           color = ~continent, 
           frame = ~year, 
           text = ~continent, 
           hoverinfo = "text",
           type = 'scatter',
           mode = 'markers')

#filtering one row results in missing Africa trace for entirety of the plot

gapminder %>% 
  group_by(year, continent) %>% 
  summarise(pop = mean(pop), gdpPercap = mean(gdpPercap), lifeExp = mean(lifeExp)) %>%
  filter(gdpPercap > 1253) %>% 
  plot_ly( x = ~gdpPercap, 
           y = ~lifeExp, 
           size = ~pop, 
           color = ~continent, 
           frame = ~year, 
           text = ~continent, 
           hoverinfo = "text",
           type = 'scatter',
           mode = 'markers')

提供された R の例とエントリポイント plot_ly() から始め、完全なデータを、フィルタリングした行および手動で追加した NAs と比較します。アニメーションフレームが欠損した観測値をどのように扱うか、また値を補完せずにトレースを表示したままにできるかを調査します。動作に明確な回避策または修正された処理が定義されれば完了です。