To Minecraft bedrock dev team, when I found this bug on my phone, I literally just switched a milk bucket in the right corner of the hotbar while started to drink it.I try to put it back to the inventory but all of a sudden,it turn back into an empty bucket that I just saw a moment ago.
Thank you for your report!
We're already tracking this issue at MCPE-54623, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated. If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
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