ant-libp2p-plaintext is used at run time in 2 crates (of which 1 optionally). It's used only as a dev dependency in 2 crates.

Depender (with downloads and own rev deps) ant-libp2p-plaintext version
110 1 ant-libp2p-swarm-test ^0.42.0
120 ant-libp2p optional ^0.42.0
110 3 ant-libp2p-relay dev ^0.42.0
110 2 ant-libp2p-dcutr dev ^0.42.0