How to install Adobe Flash Player on Ubuntu (for Firefox, Chromium, Vivaldi and Opera browsers)

Adobe Flash Player may not be used as it was a few years ago, but some websites still need it. Before Adobe stopped updating and distributing it (by the end of 2020), this was the way to install Flash Player compatible with Firefox, Chromium, Opera and Vivaldi web browsers on Ubuntu. 1. Enable Canonical partner repository.
This can be done by starting Software & Updates Enable the first one from the menu Canonical Partners On the line Other Software label:

After enabling the repository, click Close Button and then you will be asked to reload the software source-click Reload When asked.
You can also enable the Canonical Partner repository (and update the software source) from the command line using the following command:

sudo add-apt-repository "deb http://archive.canonical.com/ubuntu $(lsb_release -sc) partner"

sudo apt update #not needed for Ubuntu 18.04 and newer

2. Install Adobe Flash Player.
Now you can install Adobe Flash Player from Canonical Partners repository compatible with Chromium, Firefox, Opera and Vivaldi web browsers using the following command:

sudo apt install adobe-flashplugin

Restart the web browser and Adobe Flash Player should be available. By default it will not run, so you need to click on the Flash content to activate it. The appearance depends on the browser you use. For example, in Vivaldi, it looks like this:

You can test by visiting Adobe Flash Player and view the installed Flash version on page. In Firefox, you can also view the Flash version in use by typing: about:plugins In the address bar ( chrome://plugins The page has been removed from the Chromium-based browser).
Other ways to install Flash Player on Ubuntu:

• Install Google Chrome and run it once-it will automatically download Flash Player for Vivaldi and Opera browsers. However, this does not apply to Chromium and Firefox, and if Google Chrome is deleted or not used frequently, you will not receive Flash Player updates.
• By installing flashplugin-installer Package from multiverse repository. This will install Flash for Firefox, but will not install Flash for Chromium-based web browsers.
• downloading Download from Adobe website and install manually.

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