What does all in but the buttons mean?

The phrase "all in but the buttons" typically refers to a situation where someone has committed everything they can, except for the very last bit of something, often in a gambling context. In Poker, it means a player has bet all their chips except for a small amount, which they retain. It can also be used metaphorically in other contexts to indicate full commitment to a cause or endeavor, while still holding back a minor reserve.