Create a new extension with all the current code. It will have a dependency to editor-tool-highlighting-ui-code, so that autocompletion can be used without taking over all textareas in the wiki.
The current extension will become a single POM with dependencies to :
The Autocompletion code extension
editor-tool-highlighting-ui, in order to keep the current behaviour of the extension which replaces all textareas in the wiki with the Syntax Highlighting extension
Improvement
Major