_utf8 The POST parameter for gmail login contains a snowman character

Question

Possible duplicate:
What is the _snowman parameter in Ruby on Rails 3 for?

If you check the Gmail POST settings using Firebug or Chrome , you will see the _utf8 parameter with a value of ☃ :

 _utf8:☃ 

(see attached image if your browser does not display the value. This is a snowman, U + 2603, http://www.utf8-character.info/#!%E2%98%83 .)

Why are they doing this? Is it possible that they somehow check browser compatibility with UTF-8 ?

Answer 1

The _utf8 header along with the Unicode character should ensure that

• At least one Unicode character is sent to the server.
• Force incompatible browsers to comply with the character encoding of the form

In some cases, the _utf8 header is _utf8 to ☃, and sometimes it is ✓. That it really doesn't matter and can be arbitrarily chosen for pleasure.