Essentially, performance of worlds with the new next major update toggle enable have a significant performance drop, as expected for beta features, but just to kind of give a heads up on the issue
MCPE-164712
"Next Major Update" Toggle causes large amounts of lag
Resolved
Invalid
1
Thank you for your report!
However, this issue is Invalid.
Simply stating that "My game is laggy" is not helpful for Mojang to diagnose your issue. If you can pinpoint a specific cause when lag happens for you, please open a new report for that specific issue. If you think this might be a hardware issue please contact Community Support as they might be able to help with your issue.
Keep in mind that Mojang is constantly optimizing the game and simply playing the game provides feedback to Mojang on which parts cause performance issues.
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