Diggus Maximus provides vein mining feature, but in versions higher than 1.18.2, there're two major bugs, and this fork simply fixed them.
Made for FMN modpack.
Bugs solved:
1. "Stop on tool break" causes player with bare hand to break only two blocks.
2. When setting "maxMinedBlocks" lower than 14, "mineDiag" would cause the autopick to miss a block.
3. Vein mined single block won't be auto picked up.
Why not creating a pull request?
Because the original author isn't seemed likely to merge it in two months, as Issue #73 that created on Aug 11 still got no response.