Examine source code of ETag Stoppa

{
  "applications": {
    "gecko": {
      "id": "etag-stoppa@cm.org",
      "strict_min_version": "52.0"
    }
  },
  "author": "claustromaniac",
  "background": {
    "scripts": [
      "etag-stoppa.js"
    ]
  },
  "description": "Prevents Firefox from storing entity tags by removing ETag response headers unconditionally and without exceptions.",
  "homepage_url": "https://github.com/claustromaniac/etag-stoppa",
  "icons": {
    "32": "icons/etag32.png",
    "64": "icons/etag64.png"
  },
  "manifest_version": 2,
  "name": "ETag Stoppa",
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "version": "0.5resigned1"
}