The bug
Beds can be placed at y=255, however, beds placed at this height cannot be used and give an odd error message.
In chat, this message is
"Height limit for building is 256"which might make sense when I'm placing the bed, but not when I'm trying to use it.
In the console, the following message appears:
"2013-03-07 07:19:37 [CLIENT] [INFO] [CHAT] §7Height limit for building is 256"The "section 7" bit is obviously a glitch.
This applies to all blocks with a right-click action (repeater, comparator, lever, bed etc.). When right-clicking the upper side of a block this message appears. Any other side works fine.
Code analysis
Code analysis by @unknown can be found in this comment.
Linked issues
is duplicated by 43
MC-11748
It is impossible to adjust repeaters/comparators placed at the top of the world
Resolved
MC-42344
Can't sleep at the highest point in minecraft
Resolved
MC-52292
Player is unable to access block menus when said block is placed at y 255
Resolved
MC-64819
Can't light TNT at y=255
Resolved
MC-69883
Height limit warning appears when unnecessary
Resolved
relates to 2
Comments 45
Is duplicated by: MC-64819
It happens also when you use any item and rightclick it while looking down on the surface
Relates to MC-132816 - both can result in wastage of liquid buckets.
confirmed for 1.14 with command blocks, which don't even display the contained command when clicked on the top face if it is bordering the height limit, as well as placing armor stands
§7 means the text is output in grey.