DevHelp plugin for Geany

 This plugin embeds an API documentation browser and search functionality
 directly into Geany's user interface.
 .
 Devhelp is an API documentation browser mainly aimed at GNOME-related
 libraries, although there are Devhelp books for a wide range of library
 APIs. Check your package manager and/or Google and you should have no trouble
 finding books that can be viewed with Devhelp.
 .
 Geany is a small and lightweight integrated development environment using the
 GTK+ toolkit.