Animating the background-color property like this is not compositable for the browser, which means the animation is not smooth, and can contribute to the Cumulative Layout Shift web vital.
For now, we're removing this, and may consider re-introducing an alternative version in future based on user feedback.
Replaces the existing topic map with the experimental-topic-map made by @awesomerobot.
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Co-authored-by: awesomerobot <kris.aubuchon@discourse.org>
