When I use Iceweasel (Debian version of Firefox), I can see Chinese characters found on this page, but not when using Chromium. I instead see rectangles. This is on Debian 7 (Wheezy).
Firefox's rendering engine will substitute glyphs from other installed fonts (if it can find one with the required glyph) instead of displaying broken glyphs. Chromium will stick to the specified font(s) instead, and will display a "missing glyph" character if the glyph is not found.
This page has specific information for installing font packages on Debian.
- Chinese (both Simplified & Traditional)
- Serif: fonts-arphic-ukai
- Sans-serif: fonts-arphic-uming
- Serif: fonts-ipafont-mincho
- Sans-serif: fonts-ipafont-gothic
- All: fonts-unfonts-core
After installing these font packages, try this page as a test: https://en.wikipedia.org/wiki/Han_unification#Examples_of_language_dependent_characters
For me on Debian/Linux, Chrome refuses to recognize the embedded language meta tags, but Firefox/Iceweasel can handle.