This is probably welcome news for Firefox users on Linux though I caution those users that Firefox still doesn't sandbox plugins on Linux so I would discourage you from using Flash Player in Firefox. Google Chrome and Chromium do sandbox Google Chrome's Flash Player so I would just use either of those browsers if you need a Flash Player.
If you want to try it out on Linux Mint the steps are as follows. Be mindful this is a beta and you'll have to update it yourself manually when a new version is released.
- Uninstall the package adobe-flashplugin. You can do so with the command:
apt purge adobe-flashplugin
- Next download the new libflashplayer.so file.
- Then open your file manager and toggle to display hidden files (from View menu or press Ctrl+H). From your home directory go to the directory .mozilla/firefox/<profile>.default (<profile> is some random string of letters and numbers) and create a new directory there called "plugins". Move or copy the downloaded libflashplayer.so here. Alternatively you can do it from the terminal by opening a terminal on the directory where you downloaded the libflashplayer.so file and running the commands:
find ~/.mozilla/firefox/*.default -prune -exec mkdir {}/plugins \;
cp libflashplayer.so ~/.mozilla/firefox/*.default/plugins/
- Close any Firefox windows you still had open and start Firefox again. You can test your Flash Player version by going to https://www.adobe.com/nl/software/flash/about/.