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How You Can Change the Cursor Theme on Your Ubuntu Desktop , that is , to change the default cursor to a much bigger cursor size and then to change the color of the cursor , in this case , to “red color”

Open the Ubuntu Software app and search for ‘GNOME Tweaks’. Then, click ‘Install’.

Alternatively, run sudo apt install gnome-tweaks in a 

terminal app.

root@norizan-System-Product-Name:/home/norizan#

root@norizan-System-Product-Name:/home/norizan#

root@norizan-System-Product-Name:/home/norizan# apt-get install gnome-tweaks

Reading package lists... Done

Building dependency tree... Done

Reading state information... Done

gnome-tweaks is already the newest version (42~beta-1ubuntu2).

0 upgraded, 0 newly installed, 0 to remove and 5 not upgraded.

root@norizan-System-Product-Name:/home/norizan#

After installing GNOME Tweaks, navigate to the top-left ‘Activities’ overview. Go 

to GNOME Tweaks and open it. Once you open GNOME Tweaks, go to the 

Appearance option from the left pane. Choose a different cursor theme from the 

drop-down menu. In this case , change it from Yaru to 

Redglass