CAUTION:
Install only ONE of following three options. Installing more than one version of dump1090 will break the installation

OPTION (1): dump1090-mutability ver 1.15 (Only for Debian 9 and Ubuntu 18)
sudo bash -c "$(wget -O - https://github.com/abcd567a/fr24feed-debian-ubuntu-amd64-i386/raw/master/install-dump1090-mut-v1.15.sh)"

OPTION (2): dump1090-mutability EB_VERSION (Only for Debian 10, 11, 12 and Ubuntu 20, 22, 23 & 24)
sudo apt update
sudo apt install dump1090-mutability
sudo usermod -a -G plugdev dump1090
sudo reboot

OPTION (3) dump1090-fa (For Debian 9, 10, 11 & 12 and Ubuntu 18, 20, 22, 23, & 24)
sudo bash -c "$(wget -O - https://github.com/abcd567a/fr24feed-debian-ubuntu-amd64-i386/raw/master/install-dump1090-fa.sh)"

First determine architecture of your Computer/OS by issuing following command:
uname -m

(2.1) Download fr24feed x86_64/amd64 debian Package
wget https://repo-feed.flightradar24.com/linux_binaries/fr24feed_1.0.48-0_amd64.deb

(2.2) Install downloaded x86_64/amd64 package
sudo dpkg -i fr24feed_1.0.48-0_amd64.deb

(2.3) Download fr24feed debian i386 Package
wget https://repo-feed.flightradar24.com/linux_binaries/fr24feed_1.0.48-0_i386.deb

(2.4) Install downloaded i386 package
sudo dpkg -i fr24feed_1.0.48-0_i386.deb

(2.5) SIGNUP (for NEW installs only).
For upgrade of EXISTING installs, skip this step
sudo fr24feed --signup

(2.6) Enable & Restart fr24feed
sudo systemctl enable fr24feed

sudo systemctl restart fr24feed

(2.7) After restart of fr24feed, wait few minutes, then check status
sudo fr24feed-status

(1) CONFIGURATION OF FR24FEED
The configuration file can be edited by following command;

sudo nano /etc/fr24feed.ini

Shown below are contents of file /etc/fr24feed.ini, when following 2 conditions are met:

(1) A decoder like dump1090-mutability or dump1090-fa is installed and running on the Computer.

(2) during --signup OR --reconfigure, you have said yes to following question:

Would you like to use autoconfig (*yes*/no)

receiver="avr-tcp"
host="127.0.0.1:30002"
fr24key="xxxxxxxxxxx"
logmode="1"

bs="no"
raw="no"
mlat="yes"
mlat-without-gps="yes"

(2) CONFIGURING OF dump1090-mutability

Method 1
sudo dpkg-reconfigure dump1090-mutability

Method 2
sudo nano /etc/default/dump1090-mutability
sudo nano /usr/share/dump1090-mutability/html/config.js

(3) CONFIGURING OF dump1090-fa
sudo nano /etc/default/dump1090-fa
sudo nano /usr/share/skyaware/html/config.js

(1) TO UNINSTALL FR24FEED
To completely remove configuration and all files, give following commands:

sudo systemctl stop fr24feed
sudo dpkg --purge fr24feed
sudo rm -rf /usr/lib/fr24

(2) TO UNINSTALL dump1090-mutability (ver 1.15~dev and EB_VERSION)
To completely remove configuration and all files, give following commands:

sudo dpkg --purge dump1090-mutability
sudo apt purge dump1090-mutability
sudo apt purge lighttpd
sudo apt autoremove
sudo rm -rf /var/www/html
sudo rm -rf /etc/lighttpd
sudo rm -rf /usr/share/dump1090-mutability

(3) TO UNINSTALL dump1090-fa
To completely remove configuration and all files, give following 7 commands:

sudo dpkg --purge dump1090-fa
sudo apt purge lighttpd
sudo apt autoremove
sudo rm -rf /var/www/html
sudo rm -rf /etc/lighttpd
sudo rm -rf /usr/share/dump1090-fa
sudo rm -rf /usr/share/skyaware