Don't see Grub Customizer in system tools and can't start using gksudo

Terminal command line paste:

```
user@LC2530Sb:~/Desktop$ sudo add-apt-repository ppa:danielrichter2007/grub-customizer
[sudo] password for user: 
 This PPA contains the latest release of Grub Customizer.

sudo add-apt-repository ppa:danielrichter2007/grub-customizer
sudo apt-get update
sudo apt-get install grub-customizer
 More info: https://launchpad.net/~danielrichter2007/+archive/ubuntu/grub-customizer
Press [ENTER] to continue or ctrl-c to cancel adding it

gpg: keyring `/tmp/tmp9qs8jevh/secring.gpg' created
gpg: keyring `/tmp/tmp9qs8jevh/pubring.gpg' created
gpg: requesting key 3F055C03 from hkp server keyserver.ubuntu.com
gpg: /tmp/tmp9qs8jevh/trustdb.gpg: trustdb created
gpg: key 3F055C03: public key "Launchpad PPA for Daniel Richter" imported
gpg: no ultimately trusted keys found
gpg: Total number processed: 1
gpg:               imported: 1  (RSA: 1)
OK
user@LC2530Sb:~/Desktop$

```

Why can't I start Grub Customizer?