Ebay-font NPM | npm.io

ebay-font

ebay-font is the module used at eBay to load custom web fonts. It uses a strategy to avoid both FOUT and FOIT. This can be considered equivalent to the new CSS @font-face descriptor font-display: optional. Unfortunately, font-display is relatively new and hence its adoption among browsers is not widespread. So for now, this module leverages localStorage, FontFaceSet API and the Font Face Observer utility (as a backup if FontFaceSet API is not present) to provide the same functionality as font-display: optional.

ebay-font is paired along with eBay's custom font 'Market Sans'. But feel free to change it to any custom font URL of your choice.

Please refer to the detailed blog post "eBay’s Font Loading Strategy" for a full overview of how this module works.

Usage

ebay-font can be used along with other eBay open source modules Skin, Marko & Lasso, as well as in standalone mode. If you are in the eBay workflow environment, please follow the below steps

Install and save the module

npm install ebay-font --save

Add dependency in your page browser.json

"ebay-font/browser.json"

The module exposes a tag <ebay-font> to embed in the <head> tag of page HTML

<html>
<head>
    <ebay-font/>
    ... 
</head>
...
</html>

Note: If your website uses Content Security Policy (CSP), you can pass the CSP nonce value to <ebay-font> tag

...
    <ebay-font nonce="4AEemGb0xJptoIGFP3Nd"/>
...

Standalone

Copy paste this CSS and JavaScript tag snippet in the <head> tag of your page
Include the generated JavaScript file fontloader.standalone.js in the footer

<script async src="fontloader.standalone.js"></script>

Browser support

Chrome (desktop & Android)
Firefox
Opera
Safari (desktop & iOS)
IE8+
Android WebKit

Issues

Have a bug or a feature request? Please open a new issue

Open browser issues

Chrome — Very randomly on a new session, all font formats are getting downloaded if font-display is present in the font-face. Filed a bug to track it.