How do I play Flash websites on my Samsung Galaxy S3? Is there a way to use flash-based sites on Android? A browser? Radical app? I want to play videos on this site: 
http://www.onf.ca/explorer-tous-les-films

OS: 4.1.1
There's a HowTo at MakeUseOf.Com describing how to install Adobe flash player on JellyBean. Excerpt:


Enable unknown-sources on your device
Grab the .apk for flash player from XDA-Developers and save/copy it to your SDCard
Use a file manager (such as e.g. ES File Explorer File Manager), navigate to the place you've stored the .apk, and tap the file once. This starts the installer.


Once the installation is finished, you should be able to play flash again. However, not every browser might support it. The very same article mentions how to enable flash support in Firefox:


  Open Firefox, tap the menu button and open Settings > Plugins and choose Enabled.


That way you should be able to use it with your favorite websites.