Pressing jump and chat in the same time results in infinite jumping.
pressing jump again after that fixes the issue.
How to get constantly
press jump + chat button
after closing the chat your player will be jumping konstantly
to fix
press your jump button again
Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-25760.
Although MCPE-25760 mentions controllers, I think this is the same root issue and can be tracked as one ticket. Your additional information and observations are very useful, so if you can add them to the comments section of the parent issue it would be appreciated.
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