Examine source code of FieldFiller

{
  "manifest_version": 3,
  "name": "__MSG_extName__",
  "description": "__MSG_extDescription__",
  "version": "0.1.4",
  "icons": {
    "16": "icon/16.png",
    "32": "icon/32.png",
    "48": "icon/48.png",
    "64": "icon/64.png",
    "96": "icon/96.png",
    "128": "icon/128.png"
  },
  "default_locale": "en",
  "permissions": [
    "storage",
    "contextMenus",
    "scripting",
    "activeTab"
  ],
  "action": {},
  "commands": {
    "fill-all-inputs": {
      "suggested_key": {
        "default": "Ctrl+Shift+Y",
        "mac": "Command+Shift+Y"
      },
      "description": "__MSG_commandFillAllInputs__"
    },
    "fill-current-form": {
      "suggested_key": {
        "default": "Ctrl+Shift+Period",
        "mac": "Command+Shift+Period"
      },
      "description": "__MSG_commandFillCurrentForm__"
    },
    "fill-selected-input": {
      "description": "__MSG_commandFillSelectedInput__"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "fieldfiller@dividbzero",
      "strict_min_version": "128.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "open_in_tab": true,
    "page": "options.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "all_frames": true,
      "match_about_blank": true,
      "run_at": "document_idle",
      "js": [
        "content-scripts/page-agent.js"
      ]
    }
  ]
}