New Question -- Getting in front of the Page Load

Trying out the page-eater example, I can see while the text ‘This page has been eaten’ displays, it displays after the normal web page loads and displays for a split second.

I have had the same problem trying to program content replacing. How do I program a web extension to process the web page before it displays?

You can control when a content script runs using the “run_at” element in the “content_scripts” key.

For that example, “document_start” doesn’t work, because the script tries to access document.body, but “document_end” seems to do what you want.