Page Ruler

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "background": {
    "service_worker": "background.js"
  },
  "action": {
    "default_icon": "off.png",
    "default_title": "Page Ruler"
  },
  "content_scripts": [
    {
      "all_frames": false,
      "css": [
        "styleMeasureIt.css"
      ],
      "js": [
        "measureIt.js"
      ],
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "run_at": "document_idle"
    }
  ],
  "description": "Page Ruler is for measuring objects on web pages. Measure it width and height in pixels.",
  "manifest_version": 3,
  "name": "Page Ruler",
  "permissions": [
    "tabs",
    "storage"
  ],
  "version": "2.0.0",
  "icons": {
    "16": "ico_16.png",
    "19": "ico_19.png",
    "48": "ico_48.png",
    "128": "ico_128.png"
  },
  "web_accessible_resources": [
    {
      "matches": [
        "<all_urls>"
      ],
      "resources": [
        "injected_content.js"
      ]
    }
  ]
}