The bug
When building up from below scaffolding can go all the way up to block 255 but it then exhibits weird behaviour.
Examples
Video 1 is normal behaviour at y=254
[media]
Videos 2 and 3 are weird behaviour at y=255
[media][media]
Additional information
Starting from 19w11a, these ghost blocks create dark patches below where the scaffolding was placed and deleted.
Linked issues
is duplicated by 21
MC-143559
Scaffolding bug at height limit - Block extension does not work properly
Resolved
MC-143560
Scaffolding bug at height limit - Extended blocks do not update when intended
Resolved
MC-143718
Scaffolding at max height
Resolved
MC-143824
scaffolding bugs placing at height limit
Resolved
MC-146466
Scaffolding right click bug
Resolved
16 more links
relates to 2
Attachments
Comments 14
4 more comments
I'm resolving this issue as Cannot Reproduce, as there seems to be some general consensus that this issue is no longer existent or as widespread as it previously may have been. Please leave a comment if you're able to reproduce, and we can reopen the ticket. 🙂
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Looks like the server prohibits placing the block, but the client places it, resulting in "ghost blocks".