Which version of devuan - daedalus (oldstable), excalibur (stable), freia (testing)?

Thanks for the report.  Fixed in September 19 netinstall iso.

This isn't "how to avoid the problem" - but if you have difficulty with their picture captchas, this may be of help.
After spending about a half hour clicking on buses, traffic lights, crosswalks, bicycles, stairs, fire hydrants, cars, bridges (and probably more!), in a never-ending cycle, eventually I tried the audio captcha instead.  This took only about 5 tries to get it right, and then I could proceed.  All the sound samples had static, most were entirely unintelligible to me.  Just load a new one until you get one that you can understand.

I've got this script (for an example) from when I used to hibernate/suspend.  It might require pmtools pm-utils (as Ralph noted above).

#!/bin/bash
# Script name: /etc/pm/sleep.d/50_network
# Purpose: Restore network settings upon thaw / resume

case $1 in
  suspend|suspend_hybrid|hibernate)
    :
    ;;
  resume|thaw)
    # wait 10s for network to come back
    sleep 10
    logger -s "/etc/pm/sleep.d/50_network: Restoring network settings..."
    # restore network settings
    /usr/local/sbin/netconfig.sh
    logger -s "/etc/pm/sleep.d/50_network: Done."
    ;;
esac

Yes, there's firmware-mediatek_20260810-1_all.deb

However, I found in firmware/Contents-firmware:

/usr/lib/firmware/mediatek/mt7925/BT_RAM_CODE_MT7925_1_1_hdr.bin firmware-mediatek_20260622-1_all.deb non-free-firmware
/usr/lib/firmware/mediatek/mt7925/WIFI_MT7925_PATCH_MCU_1_1_hdr.bin firmware-mediatek_20260622-1_all.deb non-free-firmware
/usr/lib/firmware/mediatek/mt7925/WIFI_RAM_CODE_MT7925_1_1.bin firmware-mediatek_20260622-1_all.deb non-free-firmware

So it appears I need to update the Contents-firmware file to the correct version on the disc image.
Hopefully it will all be good in the next iso (check mirrors in a while)

Thanks for reporting this.  I'll update the freia installer soon...  it still was using the excalibur Contents-firmware file which I believe is the source of your issue.

Another option...

With qemu, use -nic user option, and set up networking as follows

ip address add 10.0.2.15/24 dev eth0
ip link set dev eth0 up
ip route add 10.0.2.0/24 dev eth0
ip route add default via 10.0.2.2 dev eth0

Also, your /etc/resolv.conf should contain

nameserver 10.0.2.3

From there, you should be able to apt install dhcpcd-base or whatever package(s) you want.

With virtualbox, you could change the network to bridged, and set up static networking as though it were a physical device on your LAN.  For example, if your LAN uses 192.168.1.0/24 with a gateway of 192.168.1.1 (I think this is a common default setup), you could do something like this

ip address add 192.168.1.20/24 dev eth0
ip link set dev eth0 up
ip route add 192.168.1.0/24 dev eth0
ip route add default via 192.168.1.1 dev eth0

Obviously, you'd want to use an address not in use by another device.  That was just an example.

from what I'm seeing on daedalus, nvidia-driver and nvidia-kernel-dkms are at version 535.261.03-1 (daedalus), 535.309.01-0+deb12u1 (daedalus-security), and oddly 535.216.03-2-bpo12+1 (daedalus-backports).
maybe this would work?

apt install nvidia-driver/daedalus-security nvidia-kernel-dkms/daedalus-security

Of course, you'll need to have apt working properly first.

OK.  For now it seems like you need to manually run

sh /lib/debian-installer-startup.d/S21ventoy-loop

to get your iso loop device set up properly.
Could you run the "expert install" and find out on which step does it freeze?  Are you able to change to tty4 at that point and read any debugging text?

6) re-write the excalibur netinstall iso to usb stick using a different writing program (or: burn to cd/dvd media)
There's probably a 7), 8), 9), and 10) that I haven't thought of yet, also.

My first suspicion would be to verify the download (check the sha256sum).  Secondly, verify that it was written to your boot media without any errors.  Is this a cd, usb stick, virtual machine install, something else ?  Also, which ISO file are you using?
The installer iso should allow you to press alt-F4 to view the latest ouput, there may be some debugging text there that will let you know what it's locked up on, or waiting for, or at least what succeeded last.  alt-F2 and alt-F3 will activate terminals in which you can issue commands, and alt-F1 will go back to the installer.
Another option is to do the "expert install" which will help narrow down on which point it is stuck.

There's this page, if you like trying to reproduce/fix bugs... https://bugs.devuan.org/db/ix/full.html