Random Dirt Spawns

Came across the odd "floating bamboo/cocoa beans", and then some distance away I saw these dirt blocks floating.  I found the floating bamboo/cocoa beans bug report ... but hadn't found something addressing this.  Could be related?

 

I know that dirt can some spawn in mid air, but these seem different,  In addition, once in a while the sand on the ground would pop and become an item, as if it had fallen on something?  I noticed this oddity with the bamboo and cocoa beans as well ... some of the same on the ground would just pop and become floating items.