Enlarging Libreoffice window completely with command

 You can open the LibreOffice window completely by pressing the CTRL+Shift+J keys together.

Adding an new hard disk to the file system

 The mount point must be placed in the media folder: /media/porter/mount_point otherwise the file manager won't discover the extra hard disk.

brightnessctl

 Changing the brightness of the screen of a laptop, you can use the command brightnessctl.
1. brightnessctl -l
2. brightnessctl set 5000