How do I make Chromium use Flash from Google Chrome?

THIS ANSWER IS 4 YRS OLD AND MAY NOT WORK ON NEWER SYSTEMS

Download Google Chrome and extract libpepflashplayer.so from /opt/google/chrome/PepperFlash in the Chrome deb file Copy libpepflashplayer.so to /usr/lib/chromium-browser/plugins Make the necessary changes to the Chromium startup

sudo gedit /etc/chromium-browser/default

Add this to the CHROMIUM_FLAGS

CHROMIUM_FLAGS="--ppapi-flash-path=/usr/lib/chromium-browser/plugins/libpepflashplayer.so --ppapi-flash-version=11.5.31.2"

You can get the correct version of the flash plugin from the "version": json tag in the mainfest.json from /opt/google/chrome/PepperFlash in the Chrome deb file

pepperflashplugin-nonfree is deprecated on 05/2015. They do not work for Chrome 53 and higher. You can see Getting-Flash. Ubuntu Wiki also "recommended" you to install adobe-flashplugin. Then we install adobe-flashplugin.

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

Then you should restart your browser and open chrome://plugins/. If you don't see Adobe Flash Player there, you can run the following commands.

sudo apt-get install chromium-browser
sudo apt-get upgrade

It will upgrade adobe-flashplugin for chromium or if you use chrome, do it the same way.

These instructions will install Pepper flash player for Chromium in Ubuntu 14.04 and later releases, and it will also be updated automatically. Because Google ended support for Chrome on 32-bit Linux in March, 2016, Pepper flash player can only be installed for 64-bit versions of Chromium.

To install flash player in Chromium web browser search the Dash for Software & Updates and open the Software & Updates window. Click the Other Software tab in the Software & Updates window and put a check mark in the checkbox to the left of where it says: Canonical Partners.

Click the Close button to close the Software & Updates window.

Open the terminal and type:

sudo apt remove pepperflashplugin-nonfree # remove pepperflashplugin-nonfree if it's installed  
sudo apt-get update  
sudo apt-get install adobe-flashplugin  
sudo apt install browser-plugin-freshplayer-pepperflash