TamperMonkey script to forcibly disable NSFW Reddit

reddit_nsfw_disable.user.js

// ==UserScript==
// @name         Reddit NSFW Disabler
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  WIP NSFW disabler
// @author       You
// @match        https://www.reddit.com/*
// @icon         https://www.redditstatic.com/shreddit/assets/favicon/192x192.png
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    const PAGE_BLOCKED_P_STR = `<p class="text-14 font-normal w-full mb-0">
This page is only for users 18 and older, and your account is registered as underage. You're not allowed to view it.
<br><br>
If you think it's important, talk to your parent or guardian who manages your parental controls.
</p>`;
    const SETTING_BLOCKED_STR = `
This setting is only for users 18 and older, and your account is registered as underage. You're not allowed to access or change it.
<br><br>
If you think it's important, talk to your parent or guardian who manages your parental controls.
`;

    // https://www.w3schools.com/js/js_cookies.asp
    function getCookie(cname) {
        let name = cname + "=";
        let decodedCookie = decodeURIComponent(document.cookie);
        let ca = decodedCookie.split(';');
        for(let i = 0; i < ca.length; i++) {
            let c = ca[i];
            while (c.charAt(0) == ' ') {
                c = c.substring(1);
            }
            if (c.indexOf(name) == 0) {
                return c.substring(name.length, c.length);
            }
        }
        return "";
    }

    setInterval(() => {
        (() => {
            // NSFW post detected, go to preferences if logged in or home if not
            if (document.querySelectorAll('shreddit-post[nsfw]').length > 0) {
                window.location.replace(getCookie('USER') === '' ? 'https://www.reddit.com/' : 'https://www.reddit.com/settings/preferences');
            }
        })();

        (() => {
            // Modify logged in NSFW community warning modal
            const button = document.querySelector('#nsfw-action-button');
            if (button) {
                button.style.display = 'none';
            }

            const text = document.querySelector('guard-community-modal p')?.parentElement;
            if (text) {
                text.innerHTML = PAGE_BLOCKED_P_STR;
            }
        })();

        (() => {
            // Modify the logged in NSFW post warning page
            const button = document.querySelector('confirm-over-18');
            if (button) {
                button.style.display = 'none';
                const text = button.parentElement.parentElement.querySelector('div');
                if (text) {
                    text.innerHTML = PAGE_BLOCKED_P_STR;
                }
            }
        })();

        if (window.location.pathname === '/settings/preferences') {
            // Uncheck logged in NSFW setting switch
            const pref = document.querySelector('settings-preferences');
            if (pref) {
                const checkbox = pref.shadowRoot.querySelector('faceplate-switch-input[aria-label="Show mature content (I\'m over 18)"][checked]');
                if (checkbox) {
                    checkbox.click();
                }
            }

            // Modify logged in NSFW setting change warning modal
            const desc = document.querySelector('.settings-row-modal-card > #nsfw-desc');
            if (desc) {
                desc.innerHTML = SETTING_BLOCKED_STR;
                const enableButton = document.querySelector('.settings-row-modal-card > button[slot="primary-button"]');
                if (enableButton) enableButton.style.display = 'none';
                document.querySelector('.settings-row-modal-card > button[slot="secondary-button"]')?.classList.add('button-primary');
            }
        }
    }, 500);
})();