Ensure that you have fonts that can represent the characters on the second line of the test. Ensure that the default encoding for the browser you are testing is not set to ISO 8859-15.
UTF-8 BOM vs HTML5 meta charset
Test passes if the lines below look the same.
Assertion: A page with a UTF-8 BOM will be recognized as UTF-8 even if the HTML5 meta charset declares a different encoding.
This page starts with a UTF-8 BOM, but ISO 8859-15 is declared in the HTML5 meta charset.
The text contains the following sequence of bytes: 0xC3 0xBD 0xC3 0xA4 0xC3 0xA8. The characters serve to distinguish ISO 8859-15 from ISO 8859-1, UTF-8 and UTF-16.
The graphic on the lower line shows what you would expect to see if the page is encoded as UTF-8.