The bug
Using the /setblock command to place a structure block, it sets the default mode to Save. This is inconsistent with the default mode when placing a structure block by hand, which is Load.
How to reproduce
Give yourself a structure block by running the command
/give @s structure_blockPlace it down and open its UI
✔ Notice how the default mode isLoadRun the command
/setblock ~ ~ ~ structure_blockOpen its UI
❌ Notice how the default mode isSave
Comments 5
It's a bug with the partially new system added for structure blocks, it will probably be fixed within the next snapshot.
Confirm in 20w46a