AnyBar! I finally found it. And I misremembered; it doesn't run a shell script, it just listens on a UDP port, and a shell script can send it messages to change the color of the dot.
https://github.com/tonsky/AnyBar/
PERFECT for the use case I needed this morning.
npub12y…4yv4g
2023-11-03 16:30:30
in reply to nevent1q…dthh
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npub12yf8yj84ydmh95tue6dpnh2f368xyxhktsyw3s5d3uuu2pweykyqe4yv4gSeen on
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