manifest.json

{
    "applications": {
        "gecko": {
            "id": "FANDOM-d-import@addon"
        }
    },
    "name": "Customize Discussions",
    "version": "1.4",
    "description": "Imports custom JavaScript and CSS into all Discussions on Fandom",
    "content_scripts": [
        {
            "run_at" :"document_end",
            "matches": [
                "*://*.fandom.com/d*",
                "*://*.fandom.com/f*"
            ],
            "js": [
                "js/import.js"
            ]
        }
    ],
    "permissions": [
        "activeTab",
        "storage"
    ],
    "icons": {
        "16": "img/logo16.png",
        "48": "img/logo48.png",
        "128": "img/logo128.png"
    },
    "options_ui": {
        "page": "html/options.html",
        "open_in_tab": false
    },
    "web_accessible_resources": [
        "lib/jquery-3.3.1.min.js"
    ],
    "manifest_version": 2
}