Type about:preferences#content<enter> in the address bar. Across from fonts and colors, press the Advanced button. On the bottom, turn on Allow Web Sites To Choose Their Own.

Fonts Information - Detected via Flash http://browserspy.dk/fonts-flash.php?detail=1

Many site issues can be caused by corrupt cookies or cache.

Warning ! ! This will log you out of sites you're logged in to. You may also lose any settings for that website.

• Delete cookies to remove the information websites have stored on your computer {web link}

• How to clear the Firefox cache {web link}

If there is still a problem, Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Did this help?

While you are in safe mode;

Try disabling graphics hardware acceleration in Firefox. Since this feature was added to Firefox it has gradually improved but there are still a few glitches.

How to disable Hardware Acceleration {web link}

Hi Fred, all those settings you suggest are already in place and cache has been cleared. Yet the fonts still look bizarre as per the previous screenshots.

I called for more help.

Please provide a public link (no password) that we can check out. No Personal Information Please !

This looks like there is some monospace font being used for these elements.

What font does the font Inspector show for this element ?

You can right-click and select "Inspect Element" to open the builtin Inspector with this element selected.

• https://developer.mozilla.org/en-US/Tools/Page_Inspector/How_to/Examine_and_edit_HTML

You can check in the Rules tab in the right panel in the Inspector what font-family is used for selected text. You can check in the Font tab in the right panel in the Inspector what font is actually used because Firefox might be using a different font than specified by the website.

• https://developer.mozilla.org/en-US/Tools/Page_Inspector/How_to/Edit_fonts

I checked the website and they use font-family: Courier, monospace; for CODE and PRE tags. That is likely causing this problem. You can remove the quite old Courier font from the Windows Fonts folder (i.e. uninstall this specific Courier font, you can leave Courier New) to prevent Firefox from using this font and take a better looking monospace font instead.

Hi Cor-el, thank you for your reply. It's odd because a few days ago the same site was displaying the fonts perfectly on Firefox as per Chrome. If I delete the Courier font then it will remove it across the board, which seems like the wrong way to go since the font is displaying fine in Chrome and Opera. There must be something going pete tong inside Firefox?

Weirdly I've just inspected the same site in Chrome and it serves up:

font-family: "Lucida Grande" , "Lucida Sans Unicode" , Verdana, Tahoma, Arial, sans-serif;

And I can't find any monospace font in my windows font folder!

Did you verify that Firefox is using this Courier font ?

You may have accidentally zoomed web page(s). Reset the page zoom on pages that cause problems.

• View -> Zoom -> Reset (Ctrl+0/Command+0 (zero))

• https://support.mozilla.org/en-US/kb/how-do-i-use-zoom

Does it make a difference if you enable hardware acceleration ?

Hi Cor-el, the zoom reset makes no difference. Nor does enabling hardware acceleration. Do I need to restart the browser after enabling?

The font information you posted above is used for normal text on the website. The monospace font is used for content in <pre> and <code> tags.

OK after deleting a couple of hundred fonts and still not getting anywhere, I finally waxed it by deleting the courier new (which looks like it was corrupted), downloading a fresh version of courier new, installing, deleting cache and restarting firefox..... And it's back and I can read it..... Man, that was a mission and a few hours of my life that I won't be getting back again ;)