Device: Nexus 6P
I was also able to reproduce this on Android 7.1.2 and on all the 1.2.0 betas so far.
After opening and saving a world on 1.2.0 beta, its preview screenshot in the worlds list is sheared sideways, as if the stride of the image format is incorrect. See attached screenshot.
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is duplicated by 2
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I think this applies to all screenshots provided by the game.
For my device, I think I either change the DPI or disable the status bar (meaning I must swipe down in all apps to show it) to work around the issie.
This seems to be fixed in 1.6.0 release (Nexus 6P, Android 8.1.0): worlds opened on 1.6.0 shows non-glitched screenshots; worlds that were never opened on 1.6.0 still had glitched previews.