Gmail Mass Mail Merge - GMass Emails Extension for Chrome

{
    "update_url": "https:\/\/clients2.google.com\/service\/update2\/crx",
    "name": "__MSG_extName__",
    "default_locale": "en",
    "description": "__MSG_extDescription__",
    "version": "1.0.2",
    "manifest_version": 3,
    "icons": {
        "16": "images\/gmailmassmailmerge16.png",
        "32": "images\/gmailmassmailmerge32.png",
        "48": "images\/gmailmassmailmerge48.png",
        "64": "images\/gmailmassmailmerge64.png",
        "128": "images\/gmailmassmailmerge128.png"
    },
    "permissions": [
        "identity",
        "activeTab"
    ],
    "action": {
        "default_popup": "popup.html",
        "default_icon": {
            "16": "images\/gmailmassmailmerge16.png",
            "32": "images\/gmailmassmailmerge32.png",
            "48": "images\/gmailmassmailmerge48.png",
            "64": "images\/gmailmassmailmerge64.png",
            "128": "images\/gmailmassmailmerge128.png"
        }
    },
    "content_security_policy": {
        "extension_pages": "script-src 'self'; object-src 'self'"
    },
    "oauth2": {
        "client_id": "652745226337-28pmn9e4c0gt8m50v540sgo6apladj50.apps.googleusercontent.com",
        "scopes": [
            "https:\/\/www.googleapis.com\/auth\/userinfo.profile",
            "https:\/\/www.googleapis.com\/auth\/drive",
            "https:\/\/www.googleapis.com\/auth\/spreadsheets",
            "https:\/\/mail.google.com\/"
        ]
    },
    "background": {
        "service_worker": "background.js"
    },
    "content_scripts": [
        {
            "matches": [
                "http:\/\/mail.google.com\/*",
                "https:\/\/mail.google.com\/*",
                "https:\/\/inbox.google.com\/*",
                "http:\/\/inbox.google.com\/*"
            ],
            "run_at": "document_end",
            "js": [
                "contentScript.js"
            ],
            "css": [
                "contentScript.css"
            ]
        }
    ]
}