Hi, This is still an issue.
It works after manually copying the firmware found in [1]. However, the README of this repository warns that those firmwares might have vulnerabilities (such as CVE-2018-5383, CVE-2019-9506, CVE-2020-10135): including them in Debian non-free, may not be a great idea. [1] https://github.com/winterheart/broadcom-bt-firmware/tree/master/brcm Gabriel