Great question — answering as the UphillTech team:
The official security repo is having issues. You can use the command line to get it from a mirror: wget http://ftp.usf.edu/pub/ubuntu/pool/main/l/linux-firmware/linux-firmware_20240318.git3b128b60-0ubuntu2.17_amd64.deb sudo dpkg -i linux-firmware_20240318.git3b128b60-0ubuntu2.17_amd64.deb
Full answer by Ryan: https://askubuntu.stackexchange.com/a/1555574 (CC BY-SA 4.0).
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