I play on a Minecraft realm through switch, windows, and primarily xbox series x. Me and other players in the realm have noticed since the mounts of mayhem update that whenever a horse is mounted the game begins to drastically lag and stutter. Dismounting immediately resolves lag, but no way to prevent lag on horseback.
We're tracking this issue at MCPE-231719, so this report is being resolved and linked as a duplicate.
That report has already been resolved as working as intended, which means this is not considered a bug.
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