Firefox began actively phasing out plugins. In 2017, Mozilla announced a roadmap to deprecate NPAPI plugins. By default, Firefox began requiring users to click-to-activate plugins, reducing the automatic exposure to security risks.

The final nail in the coffin came on December 31, 2020—Adobe’s official "End of Life" (EOL) for Flash Player. Following this date, Adobe blocked Flash content from running. Modern versions of Firefox no longer support the Flash plugin at all. The code that allowed Firefox to interface with Flash has been removed from the browser’s core.

They add security risk and zero benefit.

Here’s a clear breakdown of the and whether it’s still a useful feature today.

The demise of the Adobe plugin was driven by the rise of HTML5. HTML5 introduced native video and audio playback, eliminating the need for Flash to stream video. Simultaneously, CSS3 and JavaScript advanced enough to handle animations that previously required an Adobe plugin.