I had the same problem too. I constantly tried to change the value in newtab.browser.url but it wasnt succesful. I almost gave up until I saw a message on the bottom left corner of the new tab that I was opening. You open the message and select the option available which reinitiates the values for the new tab. Gone. Hope this will help someone.

I cannot change to about:blank at all. Thus I do not get any message when I next open a new tab! I find this so frustrating!!

Hi johncastre

What is the current value of the browser.newtab.url pref on the about:config page?

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Firefox/Tools > Add-ons > Appearance).

• Do NOT click the Reset button on the Safe Mode start window.

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

If you do not keep changes after a restart or otherwise have problems with preferences, see:

• http://kb.mozillazine.org/Preferences_not_saved

I can work in Safe mode but he change is lost when I go back,. I have checked the Profile folder but there is no pref.js file there at all.only a prefs file.

This is all ridiculous, expecting users to deal with this for a very simple request!!

Note that Windows hides some file extensions by default.
Among them are .html and .ini and .js and .txt, so you may only see a name (prefs) without file extension.
You can see the real file extension (type: JSCRIPT) if you open the Properties of the file via the right-click context menu.

Is there a user file as well?

This problem doens't appear to have a solution.

Glad you have come to the conclusion I was reaching..it's pretty useless change that is annoying!

OK guys, here's what I've been able to do in Windows XP. I had the exact problem since the default changes were made to "about:config" by the IT "Gurus" (tongue in cheek) at Firefox. I couldn't get "browser.newtab.url", which had a default value of "about:newtab" to save the changes when I tried to set the new value to "about:blank"

Well, here's the secret. I had an extension called something like "accelerate speed dial" in my extension list. I disabled it and, like magic, I have now saved "about:blank" as my newtab url. Safe Mode turns off all extensions so you don't know which is the interfering one. What you need to do is to disable each extension, one-by-one, in normal mode then restart Firefox each time and set "browser.newtab.url" to "about:blank" and see if it saves. Then open a new tab to verify you have found the interfering extension. So far my Firefox 25.0.1 has suffered no ill effects and my new tabs are all BLANK!!!!!!!!

Here are the steps:

1.) Disable the interfering extension in >Tools>Add-ons>Extensions then restart Firefox

2.) Open a new tab and type "about:config" in the address bar.

3.) In the Search bar type: "newtab"

4.) Locate and double click "browser.newtab.url"

5.) In the "Enter String Value" box change "about:newtab" to "about:blank" and click OK.

6.) Verify that the value has changed and now all new tabs will be blank.

Come on IT, you guys get paid for this ??? !!!