You will need a font that supports Greek.

decimal ncr outside range of charset

equal

Test passes if you the same character twice. (Font differences are irrelevant.)

β
reference image

Assertion: A decimal numeric reference containing the Unicode code point of a character which is not supported by the current character encoding still produces the intended character.

Notes:
The HTML page is served as ISO 8859-1 (covers Western Latin), but the character referenced is Greek.

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html5 as html