Plugins
Those extensions require a good understanding of the Draft.js API.
Draftail supports plugins following the Draft.js Plugins architecture. Such plugins are the most advanced and powerful type of extension for Draftail, offering customisation capabilities equal to what would be possible with a custom Draft.js editor. From the rendering of any block, to the text input handling, keyboard shortcuts, copy-paste handling – all that is customisable in a bespoke Draft.js implementation should be customisable with plugins.
Reusing existing plugins
Please follow the official Draft.js Plugins documentation for information on how to reuse existing plugins. From the Draftail perspective, this should be very straightforward; for example:
import createHashtagPlugin from "draft-js-hashtag-plugin"
const hashtagPlugin = createHashtagPlugin()
const editor = <DraftailEditor plugins={[hashtagPlugin]} />
Creating new plugins
Please have a look at the official How to create a plugin guide. You can also explore the code of many pre-existing plugins.
Example
Here is an example of a custom "action list" plugin, which uses a custom block component: