(Note: It affects all versions with Jigsaw blocks)

If player generates Jigsaw blocks using Structure Blocks, it can't generate scructures.

I excepted to...

Jigsaw block generate something.

Reproduction steps:

1. Type command /tp 1000 70 1000
2. Type command /give @p structure_block
3. Place structure block, select "Load" and type new village structure (For example, village/plains/plains_lamp_1 or village/plains/houses/plains_small_house_5)
4. Load the structure and see that Jigsaw blocks are in structure
5. See that in the GUI of Jigsaw block isn't any button of generating structure
6. Try to re-generate chunks using F3+A or /tp 0 100 0 + /tp 1000 70 1000
7. See that the structure isn't generated

NOTE: It don't matter that is there world spawn or not!

Adnotations to screenshots:

2019-01-20_09.02.20: Before F3+A (World spawn)

2019-01-20_09.02.29: After F3+A (World spawn)

All other aren't at world spawn.