Change the website favicon

The following function changes the favicon to url:

const setFavicon = function(url) {
// Find the current favicon element
const favicon = document.querySelector('link[rel="icon"]');
if (favicon) {
// Update the new link
favicon.href = url;
} else {
// Create new `link`
const link = document.createElement('link');
link.rel = 'icon';
link.href = url;

// Append to the `head` element

When you want to update the favicon dynamically, for example, to user's icon in a social website:


Use an emoji as the favicon

Note that the setFavicon() function above accepts the favicon's URL. We can have some cool thing by passing a custom URL.

In the code below, we create a canvas element, fill it with a particular emoji and get the custom URL:

const emojiFavicon = function(emoji) {
// Create a canvas element
const canvas = document.createElement('canvas');
canvas.height = 64;
canvas.width = 64;

// Get the canvas context
const context = canvas.getContext('2d');
context.font = '64px serif';
context.fillText(emoji, 0, 64);

// Get the custom URL
const url = canvas.toDataURL();

// Update the favicon

// Usage


Calculate the size of scrollbar
Check an element against a selector