问题 I'm making a Firefox add-on extension to insert a pdf document in the translated page of Google and I want to use pdf.js . Don't want to use embed or iframe tags to do it, I want to do my own pdf viewer. I'm trying to use the pdj.js library in a Firefox add-on, but it not work. I have already tried to do it adding this in manifest.json . "content_scripts": [ { "matches":["*://translate.google.com/*"], "js": ["script.js","pdf.js"] } [enter image description here][1] ] but when I do: pdfjsLib