Boomerang for Gmail

{
    "update_url": "https:\/\/clients2.google.com\/service\/update2\/crx",
    "name": "Boomerang for Gmail",
    "version": "1.8.7",
    "description": "Meeting scheduling and email management tool trusted by millions. Schedule meetings, track responses, send later, and more.",
    "background": {
        "service_worker": "background.js"
    },
    "permissions": [
        "management",
        "activeTab"
    ],
    "manifest_version": 3,
    "icons": {
        "16": "b4g_16.png",
        "48": "b4g_48.png",
        "128": "b4g_128.png"
    },
    "content_scripts": [
        {
            "matches": [
                "https:\/\/mail.google.com\/*"
            ],
            "js": [
                "b4g_message_ui.js",
                "b4g.js"
            ],
            "css": [
                "css\/b4g_message_ui.css"
            ],
            "run_at": "document_end"
        }
    ],
    "action": {
        "default_icon": {
            "19": "b4g_19.png",
            "38": "b4g_38.png"
        },
        "default_popup": "popup.html",
        "default_title": "Boomerang - Send this page later"
    },
    "web_accessible_resources": [
        {
            "resources": [
                "b4g_128.png",
                "inbox_pause_dialog.html",
                "login_dialog.html",
                "b4g_bookmarklet_1.8.2.js",
                "css\/extensionsafejqueryui_1.8.2.css",
                "css\/extensionsafestyle_1.8.2.css",
                "b4g_bookmarklet_1.8.3.js",
                "css\/extensionsafejqueryui_1.8.3.css",
                "css\/extensionsafestyle_1.8.3.css",
                "b4g_bookmarklet_1.8.4.js",
                "css\/extensionsafejqueryui_1.8.4.css",
                "css\/extensionsafestyle_1.8.4.css",
                "b4g_bookmarklet_1.8.5.js",
                "css\/extensionsafejqueryui_1.8.5.css",
                "css\/extensionsafestyle_1.8.5.css",
                "b4g_bookmarklet_1.8.6.js",
                "css\/extensionsafejqueryui_1.8.6.css",
                "css\/extensionsafestyle_1.8.6.css",
                "b4g_bookmarklet_1.8.7.js",
                "css\/extensionsafejqueryui_1.8.7.css",
                "css\/extensionsafestyle_1.8.7.css"
            ],
            "matches": [
                "https:\/\/mail.google.com\/*"
            ]
        }
    ]
}