Caseless is used at run time in 83 crates (of which 8 optionally). It is a direct run-time dependency in 13 crates. It's used only as a dev dependency in 3 crates.

Depender (with downloads and own rev deps) Caseless version
89K 130 comrak ^0.2.1
1.6K 5 rustpython-vm ^0.2.1
180 ttdl ^0.2
2 syntaxdot-encoders ^0.2
8 preftool ^0.2
3 silkenweb ^0.2.2
1 rpfm_extensions ^0.2
2 rpfm_lib ^0.2
fcd ^0.2
sortpar ^0.2
2 wordfreq ^0.2.1
2 ohnomore ^0.2
stream-httparse ^0.2.1