I was standing on a trapdoor over a grass block and said /back to go somewhere and when I said /back again to get back, I suffocated in the grass block. I thought I lost my items but when I waited for about 20 seconds, they appeared. But I couldn't pick them up and they kept bouncing into the grass block and back. I asked someone to confirm that they've seen it but after I said that, I figured I should break the grass block. Once I did that, all my items flew to me.
So if you ever suffocate...break the block you suffocated in.
._. Is this client side and not able to fix?