The sticky piston, while lying on its side (only while facing positively on the Z axis) has a broken texture on the top. Not using a texture pack of any sort, not even the beta textures.
May be related - This screenshot was taken while running latest version of the official bedrock server software.
This still does occur in the regular game, however, with the server software offline.
[media]
Thank you for your report!
However, this issue is a Duplicate of MCPE-38053.
If you have additional information, please add it to that report.
Please search before reporting, as it's likely that one exists already.
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