When we summon a FallingSand Entity, it will not display it.
If the FallingSand Time is 1, the block will appear after falling but it don't display it as an entity with in the Debug Overlay.
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is duplicated by
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Confirmed for FallingSand as wool

If you summon a FallingSand entity on a block with the same Block ID, it will take it and fall displaying it.
confirmed, both with command and spawner
thought my spawner broke
Also, when leaving a world while sand is falling, the sand disappears until it finishes falling.
I think that Minecraft can't display FallingSand entities with a tag Time:1 , because It work with a FallingSand entitiy with Time:0 (when you place a sand block, it summons a FallingSand entity with a Time:0). And I think (but I'm not sure) that when you join a world with a FallingSand Entity, it will always turn it into a FallingSand with Time:1 .
Fixed in 08a
-> Fixed in 08a
Nope, not fixed at all.
Works fine with me
I'm still getting this issue in 14w08a too, could you paste the command you're using?
Oh okay I see. The bug seems to occur only when you summon falling sand but not anymore when you place a sand block. 🙂
Yeah, I think that's pretty much always been the case; it's the bug report means when it says "summon"
Discovered something about this, if you summon a FallingSand with time not equal to 0 on a block of the proper type, the client will delete the block, but the server will not. Also the client will be able to see the FallingSand created this way.
I have this too. Unfortunately, it has not been fixed and is brought back in Minecraft 15w34d 1.9 snapshot. It works for a little while after I load up the world, but then it stops showing.
15w34d is outdated, we don't accept bugs in outdated snapshots, if it happens in the latest snapshot, reply again
Confirmed for normal sand.