This did not happen before the update to .220.
Basically, after playing in the game for a while, the framerate as shown by nvidia drops to 30 fps. This happens especially after I have walked around some highly complex scenes like where there are tons of torches.
To get back to the original 60 fps, I need to press alt-tab. I don't need to go back to the desktop, but simply by pressing them it will be back to normal for a while until it happens again.
Thank you for your report!
We're tracking this issue in MCPE-122873, so this ticket is being resolved and linked as a duplicate.
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