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Running pihole -up update FTL
[i] Downloading and Installing FTL…curl: (22) The requested URL returned error: 404
[✗] Downloading and Installing FTL
Error: URL https://github.com/pi-hole/FTL/releases/download/v4.2.3/tbd not found
It seems that the -up process is trying to download from a directory (/tbd) which is a placeholder. The command does work
curl -sSL https://github.com/pi-hole/FTL/releases/download/v4.2.3/pihole-FTL-arm-linux-gnueabihf -o pihole-FTL