I would say that this will allow you to visualize the file / feed using an editor, which means better search functions, syntax highlighting, better ability to copy code ...
But that means you need to set up editors, so firebug knows how to call it - especially, therefore, it knows how to pass data.
Edit after comment: no, I don’t see it letting you see your changes on the website, but it seems to me that it’s easier to go through the HTML code in this way, with the editor you use as a developer in your daily life.
For example, you can check what this article says: Check HTML code changes with Firebug - check the "Editing with Firebug" section.
And to use it, you must:
- select something like "
Open with editor > Configure editors " and in the dialog box specify the path to the editor - and then to edit some HTML page, select "
Open with editor > name of your editor "
(Labels may not be like this: I'm using the French version ...)