The bug
By having a piston push a shulker box right as you break it, when you place the shulker box back down, it will have the break look on it.
Another output it can have is it will automatically break whatever pushed the shulker box (blocks or pistons) no matter the hardness.
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Don't put PS4 and Bedrock under the environment tab. They are covered on MCCE and MCPE, respectively.
Confirmed for 20w15a
Update: The texture will appear on whatever block you placed where the shulker box was, and if you start mining the block while walking towards it, it'll continue the damage. So you can break a shulker box, place obsidian, walk and mine and it'll break it in a second.
Can confirm (1.13-pre6).
Note: The "breaking texture" (the texture that appears when you are breaking a block) seems to be kept in place: If we decide to place another block instead of placing the shulkerbox again, it appears to be a bit broken (e.g. a piston or a fence).
And this also works with melon instead of a shulkerbox
The "breaking texture" disappear once you've tried to mine another block.