When you right and left click a block at the same time, it is replaced by the block in your hand. This happens even if the block is in the air with no other blocks around.
What I expected to happen was...:
I expected the block to break and only get replaced if there is another block to place on.
What actually happened was...:
The block break sound occurs and the break particles show up, but the block is replaced by the one that you are holding.
Steps to reproduce:
Create a new single-player creative world
Place a block at least 2 blocks above the ground
Get a different block from the creative inventory
Right-click and left-click at the same time
The block breaking sound effect and particles occur and the new block is placed where the previous one was
This can be viewed in the attached video.
Thank you for your report!
We're actually already tracking this issue in MC-154298, so I resolved and linked this ticket as a duplicate.
However, that ticket has already been resolved. That means that this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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