When you try to visit a web page containing SWF files, the Shumway extension loads all the SWF movies or animations. But you can disable the extension if you want to use Adobe Flash Player instead of Shumway. There are no options for the Shumway extension, so there is nothing you can configure. You can see the Shumway extension installed under the Add-ons web page in Firefox that you can open by typing about:addons in the Firefox location bar. Shumway comes as an extension file that you can download and install from its github web page. Although Shumway is still under development, but you can still install it and use it in your Firefox browser. Shumway uses HTML5 for all the animation and movie playback and supports almost all the features that you would find in Adobe Flash player. For example, Chrome and Opera use their own version of Flash, Microsoft Internet Explorer also comes with its own version of Flash and now Mozilla Firefox is also developing Shumway which replaces Flash for playing SWF movies and animations. This is why many web browsers have started to create their own Flash versions or Flash alternatives. This meant that users of that browsers stayed exposed to Flash vulnerabilities until Adobe released the update. A few years ago, all the browsers depended on Adobe to release the latest updated version of Adobe Flash Player to fix some vulnerability that became known publicly.

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