What Is BIP-110 and Why Has the Bitcoin Fork Stopped Producing Blocks?

Bitcoin's BIP-110 enforcing fork has stopped producing blocks, frozen at block 961,633 while the main chain reached 961,744, a gap of 111 blocks. Only 51 of 2,016 blocks in the previous period signaled support, just 2.53%, and zero blocks have signaled since the mandatory phase began. A pseudonymous group called Roughnecks mined both BIP-110 blocks.