So, today, while I was playing on a new survival world I created, I accidentally misplaced a bed on a grass block, and the bottom part of it was on that grass block but the top part of the bed was floating. Then I tried to place it on different places randomly, and I could put it wherever I wanted; even at places where the bed would be floating. I'm not sure if this is a bug or an actual feature of Minecraft Java Edition, because I am quite a new player on this edition of Minecraft and I am more familiar with Bedrock Edition of the game. If this is an actual feature, then correct me.