Trying to place grass / bush / dead bush on grass / bush / dead bush will let you hear the sound

The sound indicates that you succefully replaced current block with the one you hold.

Why can you replace a dead bush with a dead bush, or grass with grass, or ferns with ferns etc?

You can't, so no problems here.

"The sound indicates that you succefully replaced current block with the one you hold."
So wouldn't that mean that the block was replaced?

I only hear a sound if you replace for example tall grass with ferns.

Oh ok, that's replacing a block with a different one, I though this was about replacing a block with the same block.

Well if the reporter would read and follow the Bug Report Guidelines Here and provide exact steps so we could understand what exactly he means there would be no confusion.