How to tell Firefox to render various text files directly, rather than asking for external application?

Question

When navigating to various pages that are in a text-based format, such as source code, .tex/.sty files, unix configuration files, &c, Firefox often —I think whenever it can determine the text file's MIME type— ask for an external application to render them. How can I tell Firefox to just render all such pages as plain text without external assistance?

I'm using Firefox 3.5.10 on Mac Os 10.4.

Answer 1

There's no sign of this feature being built into the browser, but there is an extension for this:

Open in Browser should do what you want.