A way to compress the "full node" blockchain. This incentivizes full nodes to run, as well as put less hardware costs on miners.
https://github.com/cyberdust/core-node/wiki/White-PaperGo to the portion on compression of the blockchain (#8) if you want to skip to the meaty part.
They are already kind of implementing the solution by increaisng the mining fees . That solution might not turn out to be good for the future causes and investments . Other solution that is on its way are the upcoming forks that would considerably help to solve the "massive" blockchain growth .