When I try to install missing plugins on terminal, the following output appears:
arif@arif-HP-Pavilion-15-Notebook-PC:~$ sudo apt-get purge ubuntu-restricted-extras
[sudo] password for arif:
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package ubuntu-restricted-extras
arif@arif-HP-Pavilion-15-Notebook-PC:~$ sudo apt-get install ubuntu-restricted-extras
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package ubuntu-restricted-extras
arif@arif-HP-Pavilion-15-Notebook-PC:~$