When you place a block in creative singleplayer with/without a empty hotbar you're going to place s random block

[mkfdj]

Cobblestone or water, this happened to me in a premade map of the city

[mkfdj]

It can also transform into water

[zardoy]

When you place a block in creative singleplayer with/without a empty hotbar you're going to place s random block #229

I think it happens only in singleplayer in old version, most probably some kind of internal server desync issue (saving issues afaik).

It can also transform into water

That sounds interesting