
I'll do a full wipe/format/re-image and try again sometime. I likely just screwed something up writing the new image I verified the checksum of the download, so it could just be a bad sd card or something like that. I am 100% certain I never went through any of those steps in the past. That seems to be the most popular result.

I'll follow the guide on v, git cloning the project at github/seemoo-lab/nexmon.git. Apparently I'm getting old I honestly do not remember ever having to do this before. Thank you for the suggestion I did some reading and it appears that is what it will take. You need to reapply the Nexmon patch to enable monitor mode every time the WiFi firmware or kernel is changed/upgraded. My pi 4B' on-board broadcom 43430 worked in monitor mode with no trouble at all until a few days ago I did a sudo apt update and sudo apt upgrade, which (for the 3rd time in 3 months) rebooted to a blank sd card.
