I’ve been running Firebug at work for a long time, it’s a really solid tool. A while ago, I started using a Monaco.ttf for Windows. I think it looks much better on my Ubuntu system, but it’s nice to have on Vista.

Firebug was apparently written for the Mac, because it uses Monaco all over the place. That would be very nice, but on Windows, a bold Monaco is a wider Monaco.  This makes the line number gutters uneven, and makes the screen flash when you scroll through text:

I finally got irritated enough to google it, and I found this post by Thomas Scholz (it’s in German, here’s Google’s translation).

The details: Firebug’s CSS files are located in its extension directory, which is probably someplace like this:

  • Vista: C:\Users{USERNAME}\AppData\Roaming\Mozilla\Firefox\Profiles{alphanumerics}.default\extensions\firebug@software.joehewitt.com\skin\classic
  • XP: C:\Documents and Settings{USERNAME}\Application Data\Mozilla Firefox\Profiles\extensions\firebug@software.joehewitt.com\skin\classic

Search-and-replace the Monaco away, and restart Firefox.