I copy pasted the Ubuntu sudo apt install line and proceeded to git clone the repo, and run ./extract-firmware on a file - which led to the following output:
Firmware Mod Kit (extract) 0.99, (c)2011-2013 Craig Heffner, Jeremy Collake
Preparing tools ...
./common.inc: line 9: autoconf: command not found
I copy pasted the Ubuntu sudo apt install line and proceeded to git clone the repo, and run ./extract-firmware on a file - which led to the following output: