How can I detect whether Unicode characters are displayed properly on my web page?

Question

I’m trying to use a reasonably esoteric Unicode character on a website — specifically “︙”. Windows XP, as far as I know, didn’t ship with a font that included a glyph for this character — the Virtual PC IE 6 test image doesn’t display it at any rate.

Is there any way I can detect whether the character is displaying properly, in case people are looking at the site using Windows XP without Arial Unicode MS installed?

An answer on a similar question suggested comparing the width of an element containing just this character with the width of an element containing an unprintable Unicode character. Unfortunately, both seem to render at the same width in browsers that display my character properly as well.

Answer 1

Try using ⋮ (⋮), which is an alternate character for the same thing (a vertical ellipsis). I'm not sure why there are two glyphs for this, and they are slightly different; in my own testing, ︙ (︙) uses circles for the dots, while the other one uses squares. That probably varies by font though. And anyway, you have to increase the font size to ridiculous sizes to notice a difference.