Resizes the YouTube player to different sizes
// ==UserScript==
/*
Resizes the YouTube player to different sizes.
Copyright (C) 2025 John Burt
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>
*/
// @name YouTube Sizer
// @author John Burt
// @namespace namespace_runio
// @version 2.01
// @description Resizes the YouTube player to different sizes
// @match https://www.youtube.com/*
// @match https://www.youtu.be/*
// @exclude https://www.youtube.com/tv*
// @exclude https://www.youtube.com/embed/*
// @exclude https://www.youtube.com/live_chat*
// @exclude https://www.youtube.com/shorts/*
// @run-at document-end
// @grant GM_setValue
// @grant GM_getValue
// @supportURL https://greasyfork.org/scripts/421396-youtube-sizer
// @icon https://i.imgur.com/9haPE5X.png
// @license GPL-3.0+
// @noframes
// ==/UserScript==
(function() {
"use strict";
//==================================================================
//Local Storage Functions
if (window.frameElement) {
throw new Error("Stopped JavaScript.")
}
function setPref(preference, new_value) {
GM_setValue(preference, new_value);
}
function getPref(preference) {
return GM_getValue(preference);
}
function initPref(preference, new_value) {
let value = getPref(preference);
if (value === null || isNaN(value)) {
setPref(preference, new_value);
value = new_value;
}
return value;
}
//==================================================================
let policy;
if (window.trustedTypes) {
policy = trustedTypes.createPolicy('default', {
createHTML: (string) => string,
});
} else {
// Fallback if trustedTypes is not supported
policy = {
createHTML: (string) => string,
};
}
//==================================================================
initPref("yt-width", 854);
initPref("yt-resize", false);
//==================================================================
// Global Variables
var maxWidth = getPref("yt-width"); // Max Width of Video
var shortcutKey = "r"; // Shortcut Key
var ytresizeCss = `.ytp-big-mode .ytp-chrome-controls .ytp-resize-button { display:none !important; }`;
//==================================================================
window.addEventListener("load", () => {
const observer = new MutationObserver(checkURL);
const e = document.querySelector("title");
if (e) {
observer.observe(e, {
attributes: true,
characterData: true,
childList: true
});
}
}, {
once: true
});
//==================================================================
function checkURL() {
waitElement("#player-container-outer").then((elm) => {
if (window.location.pathname.includes("watch")) {
if (!document.getElementById("yt-css")) {
startMethods();
createResize();
}
}
});
}
//==================================================================
function waitElement(selector) {
const element = document.querySelector(selector);
const targetNode = document.body;
const config = {
childList: true,
subtree: true
};
return new Promise((resolve) => {
const observer = new MutationObserver((mutationsList) => {
for (let mutation of mutationsList) {
if (mutation.type === "childList" && mutation.addedNodes.length > 0) {
observer.disconnect();
return resolve(element);
}
}
});
observer.observe(targetNode, config);
});
}
//==================================================================
function startMethods() {
new Promise((resolve) => {
sizeObserver(); // Size Observer
resolve();
}).then(() => {
if (getPref("yt-resize")) {
addCss(`#primary.ytd-watch-flexy:not([theater]):not([fullscreen]) { max-width: ${maxWidth}px !important; }`, "small-player");
addCss(`ytd-watch-flexy[flexy]:not([full-bleed-player][full-bleed-no-max-width-columns]) #columns.ytd-watch-flexy {max-width: 100% !important;}`, "max-player");
}
addCss(ytresizeCss, "yt-css");
controlResize(); // Create Resize Button
viewObserver(); // Video Container Observer
});
}
//==================================================================
function isCentered(element1, element2) {
const box1 = element1.getBoundingClientRect();
const box2 = element2.getBoundingClientRect();
const center1 = {
x: box1.left + box1.width / 2,
y: box1.top + box1.height / 2
};
const center2 = {
x: box2.left + box2.width / 2,
y: box2.top + box2.height / 2
};
const horizontalDistance = Math.abs(center1.x - center2.x);
const verticalDistance = Math.abs(center1.y - center2.y);
return horizontalDistance <= 1 && verticalDistance <= 1;
}
function addCss(cssString, id) {
const css = document.createElement("style");
css.type = "text/css";
css.id = id;
// Use the Trusted Type policy to create trusted HTML
css.innerHTML = policy.createHTML(cssString);
document.head.appendChild(css);
}
//==================================================================
/*Resize Video Container*/
function createResize() {
const element = document.querySelector("ytd-app");
element.dispatchEvent(
new CustomEvent("yt-action", {
bubbles: !0,
cancelable: !0,
composed: !0,
detail: {
actionName: "yt-window-resized",
disableBroadcast: false,
optionalAction: true,
returnValue: []
}
})
);
return;
}
/*Viewport Observer*/
function viewObserver() {
let movie_player = document.querySelector(".html5-video-player");
let video = document.querySelector("video");
let isCenteredMoviePlayer = isCentered(video, movie_player);
let resizeObserver = new ResizeObserver((entries) => {
window.requestAnimationFrame(() => {
if (!Array.isArray(entries) || !entries.length) { // Check Animation Frame
return;
}
for (let entry of entries) {
if (!isCenteredMoviePlayer) {
if (entry.contentRect.width !== maxWidth) {
createResize();
console.log("Player Size: " + entry.contentRect.width + " x " + entry.contentRect.height);
}
}
}
});
});
// observe the given element for changes
resizeObserver.observe(video);
}
//==================================================================
/*Saves Size Setting*/
function sizeObserver() {
const targetNode = document.head;
const config = {
attributes: true,
childList: true,
subtree: true,
characterData: true
};
const callback = function(mutationsList, observer) {
for (let mutation of mutationsList) {
if (mutation.removedNodes.length >= 1 && mutation.removedNodes[0].id === "small-player") {
setPref("yt-resize", false); // Set Resize To False
controlResize(); // Change Button Icon
createResize(); // Resize Video Container
} else if (mutation.addedNodes.length >= 1 && mutation.addedNodes[0].id === "small-player") {
setPref("yt-resize", true); // Set Resize To True
controlResize(); // Change Button Icon
createResize(); // Resize Video Container
}
if (mutation.target && mutation.target.id === "small-player") {
setPref("yt-width", maxWidth);
createResize(); // Resize Video Container
} else if (mutation.target && mutation.target.parentNode && mutation.target.parentNode.id === "small-player") {
setPref("yt-width", maxWidth);
createResize(); // Resize Video Container
}
}
};
const observer = new MutationObserver(callback);
observer.observe(targetNode, config);
}
//==================================================================
function showResizeButtonTooltip(btn, show = true) {
let tooltipTopOffset = 63; // Height Above The Button For The Tooltip
const buttonRect = btn.getBoundingClientRect(); // Get Button Position
const tooltipHorizontalCenter = buttonRect.left + buttonRect.width / 2; // Tooltip Horizontal Center
const tooltipTop = buttonRect.top + buttonRect.height / 2 - tooltipTopOffset; // Tooltip Top
const tooltip = document.getElementById("ytd-resize-tt") || createTooltip();
const tooltipText = tooltip.querySelector("#ytd-resize-tt-text");
if (show) { // Show
tooltip.style.top = `${tooltipTop}px`;
tooltipText.textContent = btn.getAttribute("aria-label");
tooltip.style.removeProperty("display");
const tooltipWidth = tooltip.getBoundingClientRect().width;
tooltip.style.left = `${tooltipHorizontalCenter - tooltipWidth / 2}px`;
btn.removeAttribute("title");
} else { // Hide
tooltip.style.setProperty("display", "none");
tooltipText.textContent = "";
btn.setAttribute("title", btn.getAttribute("aria-label"));
}
function createTooltip() {
const htmlPlayer = document.querySelector(".html5-video-player");
const tooltip = document.createElement("div");
const tooltipTextWrapper = document.createElement("div");
const tooltipText = document.createElement("span");
tooltip.setAttribute("class", "ytp-tooltip ytp-bottom");
tooltip.setAttribute("id", "ytd-resize-tt");
tooltip.style.setProperty("position", "fixed");
tooltipTextWrapper.setAttribute("class", "ytp-tooltip-text-wrapper ytp-tooltip-bottom-text");
tooltipText.setAttribute("class", "ytp-tooltip-text");
tooltipText.setAttribute("id", "ytd-resize-tt-text");
tooltip.appendChild(tooltipTextWrapper);
tooltipTextWrapper.appendChild(tooltipText);
htmlPlayer.appendChild(tooltip);
return tooltip;
}
}
//==================================================================
/*Resize Button Script*/
function setButton(btn, path) {
var pathData = {};
var ariaLabel = "";
var title = "";
if (!getPref("yt-resize")) {
pathData.d = `M 19 23 L 11 15 L 11 23 Z M 29 25
L 29 10.98 C 29 9.88 28.1 9 27 9
L 9 9 C 7.9 9 7 9.88 7 10.98
L 7 25 C 7 26.1 7.9 27 9 27
L 27 27 C 28.1 27 29 26.1 29 25
L 29 25 Z M 27 25.02 L 9 25.02 L 9 10.97
L 27 10.97 L 27 25.02 L 27 25.02 Z`;
ariaLabel = `Resize mode (${shortcutKey})`;
title = `Resize mode (${shortcutKey})`;
} else {
pathData.d = `M 25 21 L 25 13 L 17 13 Z M 29 25
L 29 10.98 C 29 9.88 28.1 9 27 9
L 9 9 C 7.9 9 7 9.88 7 10.98
L 7 25 C 7 26.1 7.9 27 9 27
L 27 27 C 28.1 27 29 26.1 29 25
L 29 25 Z M 27 25.02
L 9 25.02 L 9 10.97 L 27 10.97
L 27 25.02 L 27 25.02 Z`;
ariaLabel = `Default view (${shortcutKey})`;
title = `Default view (${shortcutKey})`;
}
path.setAttribute("d", pathData.d);
btn.setAttribute("aria-label", ariaLabel);
btn.setAttribute("title", title);
}
function createButton() {
let abtn = document.querySelector(".ytp-right-controls");
let btn = document.createElement("button");
let path = document.createElement("path");
let clickEvent = new Event("click", {
bubbles: false
});
/*Start Create SVG*/
let svg = document.createElement("svg");
svg.setAttribute("height", "100%");
svg.setAttribute("version", "1.1");
svg.setAttribute("viewBox", "0 0 36 36");
svg.setAttribute("width", "100%");
let use = document.createElement("use");
use.setAttribute("class", "ytp-svg-shadow");
setButton(btn, path); // Decide Which Button
path.setAttribute("fill", "#fff");
path.setAttribute("fill-rule", "evenodd");
svg.appendChild(use);
svg.appendChild(path);
const btnContent = svg.outerHTML;
/*Finished Create SVG*/
btn.innerHTML = btnContent;
btn.classList.add("ytp-resize-button", "ytp-button");
btn.setAttribute("id", "ytp-resize-button");
btn.setAttribute("data-tooltip-target-id", "ytp-resize-button");
abtn.insertBefore(btn, abtn.lastChild.previousSibling);
/*Tooltip Event Handlers*/
const showTooltip = (event) => {
const isMouseOver = ["mouseover", "focus"].includes(event.type);
showResizeButtonTooltip(btn, isMouseOver);
};
btn.addEventListener("click", function(e) {
e.stopPropagation();
e.preventDefault();
buttonScript();
}, clickEvent);
btn.addEventListener("mouseover", showTooltip);
btn.addEventListener("mouseout", showTooltip);
btn.addEventListener("focus", showTooltip);
btn.addEventListener("blur", showTooltip);
}
function toggleStyle(id, cssTemplate) {
const styleElement = document.getElementById(id);
if (styleElement && document.head.contains(styleElement)) {
document.head.removeChild(styleElement);
} else {
addCss(cssTemplate, id);
}
}
function buttonScript() {
toggleStyle(
"max-player",
`ytd-watch-flexy[flexy]:not([full-bleed-player][full-bleed-no-max-width-columns])
#columns.ytd-watch-flexy { max-width: 100% !important; }`
);
toggleStyle(
"small-player",
`#primary.ytd-watch-flexy:not([theater]):not([fullscreen]) {
max-width: ${maxWidth}px !important; }`
);
}
function shortScript() {
let splayer = document.getElementById("small-player");
if (document.head.contains(splayer)) {
splayer.innerHTML = `#primary.ytd-watch-flexy:not([theater]):not([fullscreen]) { max-width: ${maxWidth}px !important; }`;
} else {
addCss(smallerCss, "small-player");
}
return;
}
/*Create Resize Button*/
function controlResize() {
let buttonExists = document.getElementById("ytp-resize-button");
if (!buttonExists) {
createButton();
document.addEventListener("keydown", function(e) {
let splayer = document.getElementById("small-player");
// Common checks for all keys
if (e.altKey || e.ctrlKey || e.metaKey || e.shiftKey) return;
if (/^(?:input|textarea|select|button)$/i.test(e.target.tagName)) return;
if (/(?:contenteditable-root)/i.test(e.target.id)) return;
// Check for shortcutKey
if (e.key == shortcutKey.toLowerCase() || e.key == shortcutKey.toUpperCase()) {
e.stopPropagation();
e.preventDefault();
buttonScript();
return;
}
// Check for "x" and "z" if "small-player" is in the document head
if (document.head.contains(splayer)) {
if (e.key == "z") {
e.stopPropagation();
e.preventDefault();
maxWidth -= 20;
if (maxWidth <= 854) maxWidth = 854; // min-width
shortScript();
} else if (e.key == "x") {
e.stopPropagation();
e.preventDefault();
maxWidth += 20;
if (maxWidth >= window.innerWidth) maxWidth = window.innerWidth; // max-width
shortScript();
}
}
});
document.addEventListener("wheel", function(e) {
let splayer = document.getElementById("small-player");
let player = document.getElementById("primary-inner");
if (document.head.contains(splayer)) {
if (e.altKey || e.ctrlKey || e.metaKey) return;
if (/^(?:input|textarea|select|button)$/i.test(e.target.tagName)) return;
if (/(?:contenteditable-root)/i.test(e.target.id)) return;
if (e.shiftKey) {
e.stopPropagation();
if (e.deltaY < 0) { // Scroll Up
maxWidth += 20;
if (maxWidth >= window.innerWidth) maxWidth = window.innerWidth; // max-width
} else if (e.deltaY > 0) { // Scroll Down
maxWidth -= 20;
if (maxWidth <= 854) maxWidth = 854; // min-width
}
shortScript();
}
}
});
} else {
setButton(buttonExists, buttonExists.querySelector("path"));
}
}
//==================================================================
})();