Yhis is a example if find "firefox" in google.

Looks like a problem with fonts.

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

• Clear the Cache and

• Remove Cookies

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

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

• Cookies; Select Privacy. Under History, select

Firefox will Use Custom Settings. Press the button on the right side called Show Cookies. Use the search bar to look for the site. Note; There may be more than one entry. Remove All of them.

• Cache; Select Advanced > Network. Across from

Cached Web Content, Press Clear Now.

If there is still a problem, Start Firefox in Safe Mode {web link} A small dialog should appear. Click Start In Safe Mode (not Refresh). 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.

You will need to restart Firefox for this to take effect so save all work first (e.g., mail you are composing, online documents you're editing, etc.,) and then perform these steps:

In Firefox 54 and below:

1. Click the menu button and select Options (Windows) or Preferences (Mac, Linux).
2. Select the Advanced panel and the General tab.
3. Uncheck Use hardware acceleration when available.
4. Close Firefox completely and then restart Firefox to see if the problem persists.

In Firefox 55 and above:

1. Click the menu button and select Options (Windows) or Preferences (Mac, Linux).
2. Select the General panel.
3. Under Performance, uncheck Use recommended performance settings. Additional settings will be displayed.

   

4. Uncheck Use hardware acceleration when available.
5. Close Firefox completely and then restart Firefox to see if the problem persists.

Did this fix your problems? Please report back to us!

If the problem is resolved, you should check for updates for your graphics driver by following the steps mentioned in these Knowledge base articles:

• Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

• Upgrade your graphics drivers to use hardware acceleration and WebGL

Thank's for help. I try every thing, but same problem. I try to remove all extensions and add'ons but same. There is other sites like aliexpress where the writing do not show.

What font is Firefox trying to use if you check that on the Fonts tab in the Inspector?

You can right-click and select "Inspect Element" to open the builtin Inspector with this element selected. You can check the font used for selected text in the Font tab in the right pane of the Inspector.

• https://developer.mozilla.org/en/Tools/Page_Inspector/How_to/View_fonts

You can try to set this pref to a lower value (1 or 0) on the about:config page to lower the sandbox security setting.

• security.sandbox.content.level = 0
• close and restart Firefox to make the change effective.

If this didn't work then undo/reverse the change and reset the pref via the right-click context menu to the default value.

Cor-el thank's for help. I use "security.sandbox.content.level = 0 or 1 or 2" and all resolve problem. If use the defaut 3 the problem continue. I let the 1 are ok? goodbye

If two works for you then use that setting since this is a security feature and the lower the number the less the sandbox blocks (zero disables the sandbox).

0 - no sandbox 1 - sandbox with USER_NON_ADMIN access token level 2 - a more strict sandbox, which might cause functionality issues. This now includes running at low integrity. 3 - the strongest settings we seem to be able to use without breaking everything, but will probably cause some functionality restrictions

Thank's a lot cor-el

Did you check what font Firefox is using and where this specific font is stored on your computer?

Hello cor-el Sory, my capacity is not so big. I have done one print screen, for inicial problem, is there the information about font? This one area that are new to me. Thank's