RPi4B: modern firmware vs. Device tree loaded to 0x4000 (size 0xbe0c) [fails] vs. to 0x1f0000 (size 0xbd90) [works]?

[Robert Crowston]

> All I did was remove the device_tree_address=0x4000 from config.txt.

I wonder if this means I am falling back to the firmware embedded in u-boot, which I last built back in June.

— RHC.