I'm not sure how Firefox chooses the icon for new bookmarks that are for pages other than the current page. What I'm pretty sure does NOT happen is that Firefox does not try to retrieve the site's actual icon (favicon) in the background. However, when you visit the site, there's a reasonable chance that it will be updated.

There is no built-in option to show/hide bookmark icons. You may be able to use either an add-on or a custom style rule to suppress the icons. Did you want to hide them on the Bookmarks Toolbar, the Bookmarks Menu, or both?

There are these prefs that you can consider to set to false to disable favicons entirely.

• browser.chrome.favicons
• browser.chrome.site_icons

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

• http://kb.mozillazine.org/about:config

Actually I would prefer to stop a graphic image from being displayed as part of a tab, menu item, bookmark ect.ect., Icons, favacons or whatever.

about:config's a good friend here, thank you, but those two changes did not make a difference. Appreciate the ref to the kb article

You can expire all favicons via the Browser Console.

You can open the Browser Console (Firefox menu button or Tools > Web Developer). Toggle devtools.chrome.enabled to true on the about:config page to enable the command line in the Browser Console.

• https://developer.mozilla.org/Tools/Browser_Console

Paste the JavaScript code in the command line and press the Enter key to evaluate the code.

var fS = Components.classes["@mozilla.org/browser/favicon-service;1"]
         .getService(Components.interfaces.nsIFaviconService);
fS.expireAllFavicons();

That worked. Thank you.