There are yet some more steps (in booting) AFTER uboot has found extlinux or boot.scr
Since uboot has a somewhat generic dtb (specific to a particular cpu family),
once it loads extlinux/boot.scr, it then reads what dtb is referenced, loads it for its own use
(because that dtb is specific for that device),, then finishes setup
The kernel loads, also loads dtb to know specifics of that hardware
And then the video drivers for X have to be right, most of the rest of the hardware is generic
In 20.10 can you get a vt? ,, I mean does it get booted that far?
--edit--
And you know, anything that has ubuntu in sources.list, well you can make sure there is a display manager (sddm?)
and go wild with synaptic/apt-get.. Sometimes there is a task-(window-manger) to make it simpler,
still have to fill it out but that does 1/2 (for example,, task-xfce)
Since uboot has a somewhat generic dtb (specific to a particular cpu family),
once it loads extlinux/boot.scr, it then reads what dtb is referenced, loads it for its own use
(because that dtb is specific for that device),, then finishes setup
The kernel loads, also loads dtb to know specifics of that hardware
And then the video drivers for X have to be right, most of the rest of the hardware is generic
In 20.10 can you get a vt? ,, I mean does it get booted that far?
--edit--
And you know, anything that has ubuntu in sources.list, well you can make sure there is a display manager (sddm?)
and go wild with synaptic/apt-get.. Sometimes there is a task-(window-manger) to make it simpler,
still have to fill it out but that does 1/2 (for example,, task-xfce)