Strange animation behavior with improperly specified color

When a scatter line color is specified using rgb() with float values in [0, 1] rather than integers in [0, 255], it seems to actually produce the expected color. However, when animating a scatter trace with a constant color specified this way, it turns to black during the animation. If the animation sets redraw=True it will go back to the "correct" color after the transition completes, but if redraw=False then it stays black.

Here's a colab that demonstrates the issue: https://colab.research.google.com/drive/1enQGu6ProJg22F9KxAwsewf7UvbS3fkF?usp=sharing

I'm not sure if the correct fix to this is to make the animations work the same way as for correctly specified colors or to make incorrectly specified colors always show up as black (i.e. get cast to ints) or raise an error. The current situation results in a difficult to debug behavior.

リンクされた Colab の再現手順から始め、rgb() の float 値を使用した scatter アニメーションを redraw=True と redraw=False で比較します。アニメーション中と redraw 後で定数カラーがどのように扱われるかを追跡し、そのうえで、不正なカラー値を正規化、拒否、または一貫して処理すべきかを明らかにします。