Scaffoldings placed at y=255 don't fall, regardless of whether they're attached to a block or not until updated or clicked.
Environment
Microsoft Windows 10 Home Version 10.0.17763 Build 17763
java version "1.8.0_171"
Java(TM) SE Runtime Environment (build 1.8.0_171-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.171-b11, mixed mode)
19w12b/vanilla/snapshot
Thank you for your report!
We're actually already tracking this issue at MC-143167, so we 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.
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