tl;dr
App that only lets red light through the monitor. On Mac, has no CPU impact as it runs through display controller. Slightly different mechanisms on win/linux.
Free to install and test it out if you like it. Nothing remote in it including no telemetry. No accounts needed, totally free.
Tell me what you think (especially if it's late for you).
Screenshot of what my scren looks like:
https://x.com/cyrusradfar/status/2029478321277551005
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