How do you manipulate selected text via a Firefox extension

Question

I'm working on a Firefox extension that will manipulate highlighted text.

On a stand-alone page, I can get the selected text with:

selectedText = document.selection?document.selection.createRange().text;

Then I'd manipulate the selected text with string operations on the textarea in question. Unfortunately, that isn't possible for a plugin since I don't know where the user's selected text is.

Is there a way get the name of the element in which text is selected or to alter selected text without the name of the element?

Answer 1

selectedText = content.getSelection().toString();