Good question, but I've never seen a way to set font size to pixels within Fireworks (though that does not mean it doesn't exist - only that I haven't seen it.) The only pixel measurement option I've seen is for leading - you can choose % or px. All of the font size options I found in CS4 are only in points.
Where did you see in the online help that it can be changed in a preference dialog? Posting a link to that reference might help to track down the option if it exists. (Is it possible that the new type engine in CS4 does not offer a pixel size option?)
Here you can find the part that says you can change the unit of type in the preference dialog. It's the last "comment" in italic, I haven't been able to find it anywhere else.
the link> http://help.adobe.com/en_US/Fireworks/10.0_Using/WS3A6A1373-EB19-45f9-8400-B2DB3DD32391.ht ml
Thanks - I see it now.
I noticed in the top right corner of the page a note that says "Topic appears in: InDesign, Illustrator, Fireworks" - perhaps you can change the unit of measure for fonts in the Preferences dialog in some or all of these other tools, but not in Fireworks. It may just be a content error and not actually apply to Fireworks.
I looked at the documentation for extending Fireworks to see if text size has a pixel size attribute, and it appears that TextAttr.size only accepts point size measures:
It looks like it might be content error in the help documentation.
You can submit a bug and request for correction here:
unfortunately this seems to be true for all versions of Fireworks. I purchased the CS5 upgrade with the promise that this terrible use of points instead of pixels in FW would be resolved. I can assure you it is not.
this help page was also very lame as it first says FW default is Points, then says defaults to Pixels, then says you can change it, then says you can not change it. take a look.
Someone help..because FW only points, totally unacceptable. Im having to do my text by hand in html before I can accurately spec my image mocks because I cant tell my team what the pixel size of the font face is. and no, rendering text as paths does NOT give you an accurate unit of measure.
Don't fret! The default unit of text in Fireworks is pixels, not points.
The lack of units in FW can be confusing... and it can lead to sloppy thinking. And that particular Help page does more harm than good, because it appears to have been written for multiple applications, not just Fireworks. But if you read it with that in mind, you'll understand that Fireworks is the exception: it uses pixels as the unit for text size, and that unit cannot be changed in Preferences.
I confirmed this myself a while back, while playing with text at small sizes—including bitmap fonts, and vector fonts rendered without anti-aliasing. At the time, I thought, "Oh, pixels or points... what's the difference?" But it makes a big difference if you're dealing with a bitmap font that was designed to be rendered on an 8-pixel grid. It won't render properly if sized at 9 or 10 pixels... Anyway, points are generally larger than pixels, thanks to modern screen resolutions, and the two units are not equivalent. Fireworks is a bitmap editor, so it assumes you know that you're working with pixels, not points.