I'm not a googler or familiar with chrome or really that knowledgeable about fontconfig to be honest, (so I could be wrong! and I am curious what the answer would be from jungshik or someone who knows better than I do...) but it looks like a fontconfig issue to me.
Also seems like #36 which has an extensive discussion and some possible solutions.
I can give an in-depth explanation, from the best of my knowledge, if anyone is interested...
The page asks for Segoe UI Emoji (which we Linux users don't have installed) and so our systems look for any other font that can serve those glyphs. (Usually fontconfig is the subsystem that handles this -- fontconfig generally handles which fonts get used when on Linux).
(One can double-check that the font itself is fine by editing the page in the chrome dev-tools:)