The bug
If a rail is placed above a top half trapdoor and then the trapdoor is opened, the rail does not break until it receives a block update. This is not the case for ladders against open trapdoors when that trapdoor closes.
Credits
Special thanks to @unknown in this video for discovering that rails can be placed on top half trapdoors.
How to reproduce
Place a top half trapdoor and then a rail above it.
Open the trapdoor below the rail.
→ ❌ The rail does not break.Update a block near the rail.
→ ✔ The rail breaks.
Linked issues
Comments
violine1101
Thank you for your report!
We're tracking this issue in MC-157300, so this ticket is being resolved and linked 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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