Examine source code of PDF-Direct

{
  "manifest_version": 2,
  "name": "PDF-Direct",
  "version": "1.4.1",
  "description": "Redirects academic journal fancy PDF viewers to direct file downloads.",
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "*://*.acm.org/*",
    "*://*.acs.org/*",
    "*://*.cambridge.org/*",
    "*://*.ieee.org/*",
    "*://*.jstor.org/*",
    "*://*.nature.com/*",
    "*://*.oup.com/*",
    "*://*.plos.org/*",
    "*://*.pnas.org/*",
    "*://*.royalsocietypublishing.org/*",
    "*://*.sagepub.com/*",
    "*://*.science.org/*",
    "*://*.sciencedirect.com/*",
    "*://*.springer.com/*",
    "*://*.tandfonline.com/*",
    "*://*.wiley.com/*",
    "*://*.oclc.org/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{f2b67e28-b47e-4b3f-9c92-4a201352ff73}",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}