Email > Email address (Gecko/Firefox) Favorite

Source: https://hg.mozilla.org/mozilla-central/file/be81b8d6fae9/dom/html/HTMLInputElement.cpp

Email validator used in Gecko/Firefox for <input type="email">

Derived from a manual parser.
Firefox converts UTF-8 to punycode first - the other browsers do not.
Firefox also checks the total length and the length of domain labels. Neither of these are enforced with this pattern.

Sample Matches
Text Result
account@example.com
Group #0
account@example.com
match
@example.comno match
account@no match
account@example
Group #0
account@example
match
example.comno match