All I can think of is that Firefox's settings have been changed.
Goto Tools > Options, then the Content tab. Under "Fonts & Colors", click the Advanced button and make sure that the option "Allow pages to choose their own fonts, instead of my selection above" is selected.
Do the same for the Colors button.
See if that helps.
Mark
How do I get the page size to stay readable? I can hit View>Zoom>Zoom In or Ctrl + like 3 times. But to do this for every page I load? Is there an extension or add-in that will keep my pages large enough so that they fill the screen? I'd like to take advantage of my 23" monitor, rather than have every page centered and tiny. I have no desire to start wearing tri-focals. What's up with this? IE fills the screen, but I'd really like to dump it. Obviously, this is either a shortcoming of Firefox's or my lack of expertise with it. Please let me know. Thanks.
Win7 Professional
Firefox 3.6.6
Samsung PX-2370 monitor @ 1920 x 1080
XFX Radeon HD 5850

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