Just run this apt install command
sudo apt install pepperflashplugin-nonfree browser-plugin-freshplayer-pepperflash
After this restart your browser and check Adobe's site to verify if your Pepper flash is working and showing at least version 32.
https://helpx.adobe.com/flash-player.html
As you'll see below it will download the latest version which is currently 32 and this was not possible with the old/crappy deprecated adobe-flash plu........