Sun jitters when doDaylightCycle is false

The bug

The sun jitters when the gamerule doDaylightCycle is set to false.

How to reproduce

1. /gamerule doDaylightCycle false
2. /time set 0
3. Look at the sun.

If you cannot reproduce, look at this video: https://www.youtube.com/watch?v=L81-Sg5r8og

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Code analysis by Marcono1234 can be found in this comment.