[edit: resume from suspend either goes all black, or black with cursor. If all black, I can get black+cursor with crtl+alt+F7. But can't do anything with it]
The first issue seems common but the generally-accepted answer is to update nvidia drivers to latest (eg1, eg2), which I've done (https://ppa.launchpadcontent.net/graphics-drivers/ppa/ubuntu/, installed nvidia-proprietary-570). Nvidia 1080ti GPU fwiw.
There's the option to remove nvidia systemd script, which I guess I'll try in lieu of other solutions, but I'm wary of risking breaking things. [edit: tried, no change]
Discrete graphics settings in BIOS (eg3) shouldn't have changed since I've not changed the BIOS when upgrading from xubuntu 24.04. [edit: can't find it in the settings regardless]
I don't have screensaver or lock screen enabled (eg4).
I wonder if there's something wrong with my swap file (maybe absent?); relatedly when I get to the black lockscreen or blank login screen, and reboot with the hardware button, after grub menu I get dumped to BusyBox initramfs, which doesn't happen after I hard reboot a second time. IDK if this is all related or irrelevant (eg5)
Re swap: I only have SDDs, no HDD, 32gb RAM, and free -ght says I have an 8gb swap file. I don't have a swap partition, and don't hibernate, which this says is enough. Again this was fine on my previous install.
