Relates to: MC-230411 MC-251037 MC-251043 MC-279203
The bug
The tag #minecraft:sword_efficient is intended for controlling blocks which can be mined faster with a sword than not, but that in both cases take a nonzero amount of time to break. For some reason, grass and ferns are part of this block tag, despite it being meaningless in this sense, as grass and ferns take no time to break under any circumstances.
Having these blocks in this tag is confusing for data pack creators, and also contributes to visual bloat on the debug screen.
How to reproduce
Look at minecraft:short_grass, minecraft:fern, minecraft:tall_grass or minecraft:large_fern
Press F3
Observe the block tags
Expected results
None of these blocks would belong to the tag #minecraft:sword_efficient.
Actual results
All four of them do.
How to fix
Remove these blocks from this tag.
Can confirm.