Please let me know how to install Adobe Flash Player on Ubuntu 18.04 LTS from command prompt. I tried enabling Canonical Partners repository using the following command without any success:
sudo add-apt-repository "deb http://archive.canonical.com/$(lsb_release -sc) partner"
Here is the error message:
E: Malformed entry 53 in list file /etc/apt/sources.list (Component)
E: The list of sources could not be read.
The command you executed is incorrect.
First, run the following command to remove the malformed entry:
sudo sed -i 's/deb.*partner//g' /etc/apt/sources.list
Next, run the following command to add the partner repository:
sudo add-apt-repository "deb http://archive.canonical.com/ubuntu $(lsb_release -sc) partner"
You can see here that your entry was missing ubuntu and a blank space before $(lsb_release -sc)
Additionally, you will need to enable the multiverse repository. Run the following command:
sudo add-apt-repository multiverse
The following will install all of the flash player plugins for all the different browsers you may use:
sudo apt update
sudo apt install adobe-flash-properties-gtk adobe-flashplugin browser-plugin-freshplayer-pepperflash pepperflashplugin-nonfree