A similar question was asked here but the answer refers to something called QL Stephen, which only claims to preview files with no extension. I need something that will show previews of files with extensions that are unknown to the Finder. They are all plain-text files. And, it needs to run on Lion (10.7).
To clarify: I'm not looking for a default QL for any unknown extension, but rather for one that will preview certain specific extensions (e.g., .sps, .fort) as plain text.
You can use QuicklookStephen (https://github.com/whomwah/qlstephen). Install via Brew:
brew install qlstephen
and then reset the Quicklook plugins:
qlmanage -r && killall Finder
and you should be good to go!
Tested with both files without extension and files with "unknown" extension (e.g. .nfo)
After a quick google, maybe this is what you need?
http://hints.macworld.com/article.php?story=20071028184428583
It explains how to declare specific file types as plain text, QuickLook will use these declarations.
