inxi is available without a ppa.

However, you must enable the universe repository.

After you enable the universe repository, run the following commands to install inxi:

sudo apt update

sudo apt install inxi

Additionally, updates via the inxi -U command are disabled by default. If you have problems with the current package managed version, you can update to a more current version of the script by running the following commands:

sudo sed -i 's/ATE=false/ATE=true/g' /etc/inxi.conf

sudo inxi -U

To view the current version, run the following command:

inxi -V | grep inxi

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