Tested on W10, also noticed on other devices.
After changing worlds you are often unable to walk onto slabs and carpets. It's different depending on direction you are walking onto.
https://www.youtube.com/watch?v=k4WSYQQ5BkY
You can see in the video that I was also unable to walk in-between a carpet and slab.
Test it on play.inpvp.net (0.16.1)
Test it on play.leet.cc (0.16.1)
Test it on beta.inpvp.net (0.17)
Test it on play beta.leet.cc (0.17)
Can you confirm packets are correct on the inpvp servers? This seems very client side bug-esque.
Separately, potentially linked, with auto jump enabled you are able to stand above a 1x1 hole without falling through.
Thank you for your report!
However, this issue has been closed as Invalid.
Unfortunately we don't accept issues related to External Servers here on the bug tracker, but please add more details if you think this also happens when connecting to normal vanilla MCPE servers (realms, LAN, XBL).
I'd suggest contacting the server owner directly or seeking help on the Minecraft forums.
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