@charset vs. link charset
Test passes if there is a green rectangle below.
This test is only valid if the user agent recognises the @charset and charset attribute declarations.
Assertion: An HTTP encoding declaration for a stylesheet takes precedence over a UTF-8 signature.
The HTML page is served as ISO 8859-1. The CSS contains an @charset rule that says the file is ISO 8859-1, but the HTML link charset attribute says UTF-8.