IMPORTANT EDIT:
further inspection revealed that the Banners/Signs might be changing to Banners/Signs because the location is corrupted, as soon as i use a clone command that places another Banner/Sign to the location of the LAST Banner/Sign, after the first one got removed, it corrupts as seen in the screenshot.
this actualy might be the case, because my Tank can move back and forth via "/clone move" command, and the game doesnt like if two Banners/Signs ever existed in the same location.
you can clearly see at:
1. the hitbox of the "Banner" is formed as a Sign, as it previously was one.
2. the chat says something like: "couldnt not locate sign"
as soon as i use the SAME clone command several times.
more specific about the clone command:
i use a /clone masked move command, to move a structure (Tank) relative to me two blocks ahead (north, south, west or east), keep in mind that
the structure is inside the loaded chunks.
if i use the clone command more then arround 4 times, the chat creates:
"couldnt not locate sign" for every Sign OR Banner insides the cloned
location, as seen in the screenshot.
>>> What I expected to happen was...:
the sings and banners should,ve been clone correctly to the set location
>>> What actually happened was...:
the signs and banners eyther swapped places or changed into a sign OR banner with the error messge in the chat
>>> Steps to Reproduce:
1. make shure you died once and spawned somewhere completely different than you actualy spawned first (it might be the reason)
in a "redstone ready" flat-world
2. be in the positive X and Z coordinates
3. crate a command inside a command block that is supposed to clone a location, relative to you, including Signs and banners 2 blocks further away.
!!! make shure that the command is executed every time you want to move the structure, that is nearby you, a few blocks further, so that the locations of the
front sign/banner and the back sign/banner WILL swap theyr places soon.
4. or just download the save file, go into one of the tanks and press the same wooden button over and over again.
OUTCOME:
as seen in the screenshot
FIX INGAME:
reloading the world helps
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Ticket resolved as incomplete, because no answer in a reasonable amount of time (1+ year), if it still happens, please update the ticket.
Is this still an issue in the current Minecraft Snapshot 15w49b or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.