Maintainers for firmware-nonfree are Debian Kernel Team <debian-kernel@lists.debian.org>.
You may want to refer to the following individual bug pages: firmware-adi, firmware-amd-graphics, firmware-atheros, firmware-bnx2, firmware-bnx2x, firmware-brcm80211, firmware-cavium, firmware-cirrus, firmware-intel-graphics, firmware-intel-misc, firmware-intel-sound, firmware-intelwimax, firmware-ipw2x00, firmware-ivtv, firmware-iwlwifi, firmware-libertas, firmware-linux, firmware-linux-nonfree, firmware-marvell-prestera, firmware-mediatek, firmware-misc-nonfree, firmware-myricom, firmware-netronome, firmware-netxen, firmware-nvidia-graphics, firmware-qcom-media, firmware-qcom-soc, firmware-qlogic, firmware-ralink, firmware-realtek, firmware-samsung, firmware-siano, firmware-ti-connectivity.
You might like to refer to the firmware-nonfree package page, or to the Package Tracking System.
If you find a bug not listed here, please report it.