When the Command block is at the top of the world, you can't use it by right-clicking on its upper part.
What I expected to happen was...:
Open the interface and edit the command
What actually happened was...:
All the buttons are grayed out except "Cancel"
Steps to Reproduce:
1. Place a command block at y = 255
2. Right click its upper part
Thank you for your report!
We're actually already tracking this issue in MC-11211, so I resolved and linked 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.
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