Last night I have done a Chrome extension. It’s about live searching on Facebook groups to avoid duplicate posts.
The extension returns to you the most relevant results based on your search words.
The extension do the search after backspace or return key press.
The source code can be found here and the extension can be downloaded from the
Chrome Web Store (Facebook requested takedown even the Chrome Web Store is full of unofficial facebook related extensions) or Firefox Addons.
LE: Chrome extension available again.