Terminate Firefox Processes from Linux Terminal after the Window is Closed

• 1 vim ~/.bashrc
  
• 2 alias kf='pkill -ei --signal TERM firefox && sleep 10 && pkill -ei --signal KILL firefox'
  
• 3 source ~/.bashrc
  
• 4 kf
  
• N -e prints the PID of each process
  -i case insensitive
  The TERM signal is used to request a graceful shutdown of the process.
  

References

• https://man7.org/linux/man-pages/man7/signal.7.html
• https://linuxreviews.org/Bash_Guide_for_Beginners_Chapter_12._Catching_signals
• https://turnoff.us/geek/dont-sigkill/