Extensions are a family of recipes that allow for easier installation and configuration. See ExtensionHub to install the configuration panel and ExtensionDesign on how to create or adapt a recipe to the expected structure. The list below contains compatible extensions.

Cookbook /
BootstrapIcons  BootstrapIcons extension for PmWiki (Beta)
CodeHighlight  Syntax highlighting for programming languages (Beta)
ExtensionDesign  How to create extensions compatible with ExtensionHub (Experimental)
ExtensionHub  Configuration panel for extensions (Experimental)
Filterable  Search box for long lists and tables (Beta)
InputStar  Input control shaped like a group of 5 stars. (Beta)