A low-tech solution to a high-tech problem! Automatically clicks YouTube's "Dark Mode" button if dark mode isn't already active.
// ==UserScript==
// @name Automatic Material Dark-Mode for YouTube
// @namespace SteveJobzniak
// @version 1.7.0
// @description A low-tech solution to a high-tech problem! Automatically clicks YouTube's "Dark Mode" button if dark mode isn't already active.
// @author SteveJobzniak
// @homepage https://greatest.deepsurf.us/scripts/32954-automatic-material-dark-mode-for-youtube
// @license https://www.apache.org/licenses/LICENSE-2.0
// @contributionURL https://www.paypal.me/Armindale/0usd
// @match *://www.youtube.com/*
// @exclude *://www.youtube.com/tv*
// @exclude *://www.youtube.com/embed/*
// @run-at document-end
// @grant none
// @noframes
// ==/UserScript==
(function() {
'use strict';
/* --- START: Utils-MultiRetry v1.1 by SteveJobzniak --- */
/* Performs multiple retries of a function call until it either succeeds or has failed all attempts. */
var retryFnCall = function(fnCallback, maxAttempts, waitDelay) {
// Default parameters: 40 * 50ms = Max ~2 seconds of additional retries.
maxAttempts = (typeof maxAttempts !== 'undefined') ? maxAttempts : 40;
waitDelay = (typeof waitDelay !== 'undefined') ? waitDelay : 50;
// If we don't succeed immediately, we'll perform multiple retries.
var success = fnCallback();
if (!success) {
var attempt = 0;
var searchTimer = setInterval(function() {
var success = fnCallback();
// If we've reached max attempts or found success, we must now stop the interval timer.
if (++attempt >= maxAttempts || success) {
clearInterval(searchTimer);
}
}, waitDelay);
}
};
/* --- END: Utils-MultiRetry by SteveJobzniak --- */
/* --- START: Utils-ElementFinder v1.3 by SteveJobzniak --- */
/* Searches for a specific element. */
var findElement = function(parentElem, elemQuery, expectedLength, selectItem, fnCallback) {
var elems = parentElem.querySelectorAll(elemQuery);
if (elems.length === expectedLength) {
var item = elems[selectItem];
fnCallback(item);
return true;
}
//console.log('Debug: Cannot find "'+elemQuery+'".');
return false;
};
var retryFindElement = function(parentElem, elemQuery, expectedLength, selectItem, fnCallback, maxAttempts, waitDelay) {
// If we can't find the element immediately, we'll perform multiple retries.
retryFnCall(function() {
return findElement(parentElem, elemQuery, expectedLength, selectItem, fnCallback);
}, maxAttempts, waitDelay);
};
/* Searches for multiple different elements and uses the earliest match. */
var multiFindElement = function(queryList, fnCallback) {
for (var i = 0, len = queryList.length; i < len; ++i) {
var query = queryList[i];
var success = findElement(query.parentElem, query.elemQuery, query.expectedLength, query.selectItem, fnCallback);
if (success) {
// Don't try any other queries, since we've found a successful match.
return true;
}
}
return false;
};
var retryMultiFindElement = function(queryList, fnCallback, maxAttempts, waitDelay) {
// If we can't find any of the elements immediately, we'll perform multiple retries.
retryFnCall(function() {
return multiFindElement(queryList, fnCallback);
}, maxAttempts, waitDelay);
};
/* --- END: Utils-ElementFinder by SteveJobzniak --- */
/* Automatically enables YouTube's dark mode theme. */
var enableDark = function() {
// Refuse to proceed if the user is on the old non-Material YouTube theme (which has no dark mode).
// NOTE: This is just to avoid getting "error reports" by people who aren't even on YouTube's new theme.
var oldYouTube = document.getElementById('body-container');
if (oldYouTube && document.body.id === 'body') {
var errorMessage = 'You are using the old YouTube theme. Enable the new theme <a href="https://youtube.com/new" style="color:#fff;text-decoration:underline">here</a>.';
var errorDiv = document.createElement('div');
errorDiv.style.position = 'fixed';
errorDiv.style.bottom = 0;
errorDiv.style.left = 0;
errorDiv.style.width = '100%';
errorDiv.style.padding = '10px';
errorDiv.style.textAlign = 'center';
errorDiv.style.fontSize = '130%';
errorDiv.style.fontWeight = 'bold';
errorDiv.style.color = '#fff';
errorDiv.style.backgroundColor = 'rgba(244, 67, 54, 0.9)';
errorDiv.style.zIndex = '99999';
errorDiv.innerHTML = errorMessage;
document.body.appendChild(errorDiv);
return;
}
// Wait until the settings menu is available, to ensure that YouTube's "dark mode state" and code has been loaded...
// Note that this particular menu button always exists (both when logged in and when logged out of your account),
// but its actual icon and the list of submenu choices differ. However, its "dark mode" submenus are the same in either case.
retryFnCall(function() {
// The menu button count varies based on the browser. We expect to find either 2 or 3 buttons, and the settings menu
// is always the last button (even when logged in). Sadly there is no better way to find the correct button,
// since YouTube doesn't have any identifiable language-agnostic labels or icons in the HTML. Sigh...
var buttons = document.querySelectorAll('ytd-topbar-menu-button-renderer button');
if (buttons.length !== 2 && buttons.length !== 3) {
return false; // Failed to find any of the expected menu button counts. Retry...
}
var settingsMenuButton = buttons[buttons.length - 1];
// Check the dark mode state "flag" and abort processing if dark mode is already active.
if (document.documentElement.getAttribute('dark') === 'true') {
return true; // Stop retrying...
}
// We MUST open the "settings" menu, otherwise nothing will react to the "toggle dark mode" event!
settingsMenuButton.click();
// Wait a moment for the settings-menu to open up after clicking...
retryFindElement(document, 'div#label.style-scope.ytd-toggle-theme-compact-link-renderer', 1, 0, function(darkModeSubMenuButton) {
// Next, go to the "toggle dark mode" settings sub-page.
darkModeSubMenuButton.click();
// Wait a moment for the settings sub-page to switch...
retryFindElement(document, 'ytd-toggle-item-renderer.style-scope.ytd-multi-page-menu-renderer', 1, 0, function(darkModeSubPageContainer) {
// Get a reference to the "activate dark mode" button...
retryFindElement(darkModeSubPageContainer, 'paper-toggle-button.style-scope.ytd-toggle-item-renderer', 1, 0, function(darkModeButton) {
// We MUST now use this very ugly, hardcoded sleep-timer to ensure that YouTube's "activate dark mode" code is fully
// loaded; otherwise, YouTube will be completely BUGGED OUT and WON'T save the fact that we've enabled dark mode!
// Since JavaScript is single-threaded, this timeout simply ensures that we'll leave our current code so that we allow
// YouTube's event handlers to deal with loading the settings-page, and then the timeout gives control back to us.
setTimeout(function() {
// Now simply click YouTube's button to enable their dark mode.
darkModeButton.click();
// And lastly, give keyboard focus back to the input search field... (We don't need any setTimeout here...)
retryFindElement(document, 'input#search', 1, 0, function(searchField) {
searchField.click(); // First, click the search-field to force the settings-panel to close...
searchField.focus(); // ...and finally give the search-field focus! Voila!
});
}, 30); // We can use 0ms here for "as soon as possible" instead, but our "at least 30ms" might be safer just in case.
});
});
});
return true; // Stop retrying, since we've found and clicked the menu...
}, 120, 50); // 120 * 50ms = ~6 seconds of retries.
// Alternative method, which switches using an internal YouTube event instead of clicking
// the menus... I decided to disable this method, since it relies on intricate internal
// details, and it still requires their menu to be open to work anyway (because their
// code for changing theme isn't active until the Dark Mode settings menu is open),
// so we may as well just click the actual menu items. ;-)
/*
var ytDebugMenu = document.querySelectorAll('ytd-debug-menu');
ytDebugMenu = (ytDebugMenu.length === 1 ? ytDebugMenu[0] : undefined);
if( ytDebugMenu ) {
ytDebugMenu.fire(
'yt-action',
{
actionName:'yt-signal-action-toggle-dark-theme-on',
optionalAction:false,
args:[
{signalAction:{signal:'TOGGLE_DARK_THEME_ON'}},
toggleMenuElem,
undefined
],
returnValue: []
},
{}
);
}
*/
// Also note that it may be possible to simply modify the YouTube cookies, by changing
// "PREF=f1=50000000;" to "PREF=f1=50000000&f6=400;" (dark mode on) and then reloading the page.
// However, a reload is always slower than toggling the settings menu, so I didn't do that.
};
if (document.readyState === 'complete') {
enableDark();
} else {
document.addEventListener('readystatechange', function(evt) {
if (document.readyState === 'complete') {
enableDark();
}
});
}
})();