Rated 4 out of 5 stars
This add-on appears to work fine.
I wanted to report 2 small issues (bugs) with this add-on, but there is no support contact information on the add-on page or on the author page.
1) The window (dialog box) this add-on ("HTML Elements") displays its result (output) in needs to be resizable, and it needs to have scrollbars.
Currently, the window is NOT scrollable (no scrollbars), has a fixed (fairly narrow) width, and the height of the window is as tall as it needs to be to display the result.
If the webpage that this add-on is processing is more than the very simplest sort of webpage, then the output window becomes very tall, much taller than the height of the computer screen. And since the window cannot be resized and does NOT have scrollbars, the bottom portion of the output window cannot be viewed.
2) Sometimes, after closing the output window, a small error window opens up.that says:
"Firefox cannot find the file at