The bug
The Cinematic Camera keeps its motion when switching worlds or servers. Expected would be that its motion is reset.
Reproduction steps
Assign a key to "Toggle Cinematic Camera" near the bottom of the "Controls..." settings
Open a world, activate the Cinematic Camera and start spinning
Close the world and open a different one
❌ The camera still has the remaining motion from the previous world
See
[media]
@@unknown, I have rewritten your report a little bit and have attached a video showing this issue in Vanilla Minecraft. As pointed out by @unknown, we generally do not accept reports about modded games because we cannot be sure then that the bug has not been introduced by the mod. Therefore please always try reproducing issues in unmodded Minecraft.