I am uploading some screenshots to show you the difference between Safe Mode and Normal Mode. I also tested on another computer and it looks like my Firefox in Safe Mode. So, how do i fix it? :)

I have the same issue. Everything looks messed up small when compared to the previous version of FF and Chrome or IE.

Please fix, i can't use Firefox now because it gives me headaches.

In Firefox 4 Safe mode disables extensions and disables hardware acceleration.

• Tools > Options > Advanced > General > Browsing: "Use hardware acceleration when available"

Try to toggle some of the Boolean gfx.font_rendering prefs on the about:config page to disable some features.
Filter: gfx

To open the about:config page, type about:config in the location (address) bar and press the "Enter" key, just like you type the url of a website to open a website.
If you see a warning then you can confirm that you want to access that page.
You can use the Filter bar at to top of the about:config page to locate a pref more easily.

I am seeing this as well. It seems to have happened after the latest Windows 7 updates. HElp!

Thank you! Disabling hardware acceleration fixed my issue. Now the fonts are displayed correctly! I just hope Mozilla team will find a way to be able to use hardware acceleration and display the right fonts!

I tried this and it did not solve the problem. These are the new settings (the defaults are the opposite for each of these):

gfx.font_rendering.cleartype.always_use_for_content;true gfx.font_rendering.cleartype.use_for_downloadable_fonts;false gfx.font_rendering.directwrite.enabled;true gfx.font_rendering.directwrite.use_gdi_table_loading;false

The font change is particularly noticable on facebook, where the fonts are already small and are now smaller because of this bug.

Same problem with Firefox 5, but fonts display just fine in Minefield (x64 7a) and as above works ok in safe mode.

I have tried re-installing, resetting fonts, turning hardware acceleration off, disabling and uninstalling Personas add-on. None of those have worked.

so far affecting a few of my regular sites. e.g. www.bbc.co.uk news pages.

screenshots of my problem FF5 Fonts here

Problem just being ignored by Mozilla, no official response that this is being looked at? now started getting this on my work machine too!

Both are running Windows 7 x64 SP1.

Can somebody post a link to an old Firefox 4 download all searches seem to route back to downloads for FF5 only :/

Installed 3.6 again and that works fine, now the fonts are FUBAR in Minefield (x64 7a) !!! wtf?

It appears the problem is with Windows 7 update - http://forums.whirlpool.net.au/archive/1729318 KB2545698

I have since today the same problem, I installed Windows 7 Updates, and now the fonts looks very small, specially in Facebook (very small!!!), I tried to do a Restore System, but it doesn't work (doesn't finished it :S), so, now I don't know what to do! And I don't wanna use Chrome, I love Firefox!

You can find almost every version of Firefox here, look at the right-side bar:

http://filehippo.com/download_firefox/
ftp://ftp.mozilla.org/pub/mozilla.org/firefox/releases/

(please only post links to the official Mozilla servers for downloading Firefox - c)

This same phenomenon occurred to me too, when I installed Firefox on my new PC (Win 7 x64 SP1), but after downgrading to FF 4.0.1, it stayed the same, so it's likely that SP1 has an update that makes hardware acceleration available for the browser.

It's especially annoying on the Facebook wall feed (font: Tahoma) and YouTube messages (font: Arial), if I zoom in to maximum, I can see that the font itself is right, but at normal size, it's rendered in a weird way. Just like on MonkY's screenshots.

Please, Mozilla and Microsoft, fix this issue!