Universal Age Auto-Fill

Autofills annoying age verification fields (e.g. Steam) with your birthday.

Install

Install with this link

(requires a userscript manager like Violentmonkey)

Configure

Edit the following three lines to your birthday:

const DEFAULT_YEAR = "1990";
const DEFAULT_MONTH = "1";   // January-December (1-12)
const DEFAULT_DAY = "1";