If anyone's up to it, I'd love to have a mod that mimics Terrafirmacraft's cave ins and supports to prevent block collapse for 1.12.2. Preferably it would have a config/json option for blocks that can fall and their probability of falling when a neighboring block is broken, as well as which blocks can act as supports to prevent block collapse and their radius of effect.
Conceptually, falling blocks could chain to other neighboring blocks to cause a larger area of collapse, with diminishing chances of chaining each time it passed on.
Ideally, support blocks would need to be build in columns from the floor to the ceiling. Bonus points if you can get it to detect arches of support blocks too.