Here's the promised follow-up.
- Installed adb and fastboot on my Ubuntu 22.04 Dell 'production' laptop.
- Samsung Tab A 8.4 went willingly into 'Developer Mode' and 'USB debugging', but will not go into 'OEM unlock'--that option never appears.
- There were a lot of dark alleys on the interwebs that might have led to unlocking, but none of them panned out.
After a lot of research, it appears that my particular tablet is NOT supported, and I am abandoning this "LineageOS on my tablet" project.
- Installed adb and fastboot on my Ubuntu 22.04 Dell 'production' laptop.
- Samsung Tab A 8.4 went willingly into 'Developer Mode' and 'USB debugging', but will not go into 'OEM unlock'--that option never appears.
- There were a lot of dark alleys on the interwebs that might have led to unlocking, but none of them panned out.
After a lot of research, it appears that my particular tablet is NOT supported, and I am abandoning this "LineageOS on my tablet" project.
Throwback to the BSD days: Playing with Linux, trying to plan my changes