A datapack which wlowly expands the World Border whenever players are online, then pauses its expansion when players leave.
Currently, the border is set to 128x128 blocks when the datapack first loads. It then expands depending on the number of players online:
- 0 players online: no expansion
- 1 player: no expansion
- 2 players: expands by 0.000111 blocks / tick = 8 blocks / hour
- 3+ players: expands by 0.000222 blocks/tick = 16 blocks / hour