legacy.md

Support for legacy browsers

The polyfill works in browsers after September 2020 by default (e.g. Safari 14).

If you want to support older browsers, you have to transpile temporal-polyfill-lite itself and inject polyfills for APIs used by it.

features after ES2015 used by this polyfill

BigInt

The polyfill doesn't rely on BigInt internally, so it works fine even in browsers without support for BigInt, unless you explicitly use APIs accepting or returning BigInt (such as epochNanoseconds getters).

syntax

• exponentiation operator (**): baseline 2017
• spread syntax (...) in object literal: baseline 2020
• optional catch binding in catch statement (try {} catch {}): baseline 2020
• optional chaining operator (?.): baseline 2020
• nullish coalescing operator (??): baseline 2020
• logical OR assignment operator (||=): baseline 2020
• nullish coalescing assignment operator (??=): baseline 2020

runtime

• Array.prototype.includes: baseline 2016
• String.prototype.padStart: baseline 2017
• String.prototype.padEnd: baseline 2017
• Object.getOwnPropertyDescriptors: baseline 2017
• globalThis: baseline 2020
• String.prototype.matchAll: baseline 2020

If you want to handle time zones:

• timeZone option in Intl.DateTimeFormat constructor: baseline 2017
• Intl.DateTime.prototype.resolvedOptions: baseline 2017
• Intl.DateTimeFormat.prototype.formatToParts: baseline 2018

If you want to use islamic-umalqura, persian, chinese, or dangi calendars:

• calendar option in Intl.DateTimeFormat constructor: baseline 2021