Third-party plugins let K-Meleon render types of content that it can't natively handle, like Adobe Flash content. They use the the Netscape Plugin Application Programming Interface (NPAPI) which was an industry standard until 2015. Plugins are not quite the same as extensions that expand K-Meleon's features. When possible it is more secure to use external applications than plugins.

Plugins were once a popular way to add functionality to web pages and many older webpages still cannot be accessed without a plugin. Common web browsers have dropped support for NPAPI plugins, but K-Meleon still supports third-party plugins including:

• Sun's JavaPlugin
• Adobe's FlashPlugin
• RealNetworks' RealPlayerPlugin for some media formats.
• PDF reader plugins
• QuickTimePlugin
• Silverlight (from Microsoft.com)
• Windows Media Player for Netscape

Many additional plugins are available from K-Meleon Extension Central.

K-Meleon specific tips (from archive) are available from the PluginDoc site (from Archive).

See also the page "Third-party plugins in K-Meleon (from archive)", by Andres Aule.