Start Firefox in Safe Mode {web link}

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

If I could repeat the problem on a given web page I would try your suggestion. The problem is, once I close and reopen the browser the page will load correctly. I have no idea when this will occur. I can have a page on one tab that displays garbled text, I open a new tab and go to a different web page and it will display correctly. If I refresh the first page it remains garbled.

I will try to open a garbled page in a new tab, same session, to see if it too is garbled.

I have most of the Preferences set to the default recommended by Firefox, including the font.

Go figure.

Use these links to create a new profile. Use this new profile as is. Is the problem still there?

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

http://kb.mozillazine.org/Profile_folder_-_Firefox#Navigating_to_the_profile_folder

https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Type about:profiles<enter> in the address bar.

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

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

I had the problem show when I was using Wiki-pedia. I did an initial search for "P51 Mustang Weight". The result page displayed correctly. When I selected the Wiki-pedia link the entire page was garbled.

Per cor-el's suggestion, I used the Inspect Element (right mouse click on the area to inspect) and noted that the programming was looking for a san-serif font. I checked the Preferences on the browser and noted that the Proportional font style was set to serif. I made the change and the page immediately displayed correctly.

Thanks for the suggestion. I suspected it was something with fonts but forgot about the Inspect Element tool.

Hopefully future pages will behave.

One last suggestion to anyone on a Mac having this issue. When you do Inspect Element, you will be shown what fonts are acceptable to the element. If one of the fonts does not reside in your System or User Fonts, you will see the garbled font. You cannot add to the System fonts therefore put it in the User/font directory.

The browser ought to work without user intervention required.