Recently, I noticed that my web browsers (Chrome, Firefox) are using a strange font for all the sans-serif/helvetica/arial/etc. text. I believe it's FreeSans, after inspecting a bunch of fonts. It looks "boxier" than what I believe was the original OS default; see screenshot for examples of what I'm seeing. My OS is Ubuntu 10.04.
Any ideas on how to debug this? Thanks in advance for any answers.
Are you sure that this is a different font than the system default one? It seems that you don't have Arial on your system, so the browsers are falling back to the system default font. Remember, Arial isn't a free font, so it isn't bundled with GPL operation systems like Ubuntu. And Helvetica is a popular font in professional design, but it doesn't come bundled with Windows or with popular software packages, so most systems don't have it at all.
If you want to use another, nicer font as the system font, open "Appearance" under "Preferences", and on one of the tabs, you can change the default font for the whole system. If you want to keep your system font, but want to the pages written for Arial rendered in Arial, you have to find an Arial font file (the easiest place is the font directory of a Windows installation, although this choice probably doesn't agree with copyright law) and copy it into ~/.fonts on your computer. Probably you'll also need to restart the computer or at least the X server.
I installed a fresh Ubuntu system and copied over arial.ttf from a Windows box, and saw for myself that Ubuntu is simply rendering Arial very differently from how it appears in Windows (at least at font sizes around 10-12 pt). In particular, the characters look a lot "fatter" and more "boxy" than their more slender and smoothly rounded Windows counterparts. The appearance strongly resembled that of FreeSans and Liberation Sans, causing me to lose my mind for a few hours until I was able to do this experiment on a fresh OS install.
Also, I found this to be helpful in organizing my thinking: http://neugierig.org/software/chromium/fonts/
