I went to rename some bone blocks in the anvil for a project at my base and when putting in a stack of 64 blocks and going to re-name them, the Anvil only shows 1 block for output and when you take it, the 64 blocks are still in the anvil and no re-named blocks come out but a level I tried it with dirt in case it was just the one type of blocks. Same issue. It also takes the experience level.