If you log out of Gmail, then clicking the thumbnail should take you to a login page. If you don't log out, then anyone can access your email just by typing gmail.com in the URL bar. But you're right that the picture does create a temptation to click...

You can set the new tab page back to blank if you prefer. However, please note that the page thumbnails are stored in the browser cache, so you also need to clear your cache to flush out existing thumbnails if you don't want anyone to be able to see them.

More info: New Tab Page > How to turn the new tab page off.

Clearing cache:

orange Firefox button or Tools menu > Options > Advanced

On the Network mini-tab > Offline Storage : "Clear Now"

Hi Amanda,

It seems that you are seeing Gmail in the New Tab grid (one of the 9 boxes). This is unrelated to the fact that somebody can or can not access to your inbox, it's just a "link" to Gmail.

If you want to remove that box, you can simply click on top right corner of the Gmail box (as soon as you put your mouse over the box you will see a cross in that corner).

That said, removing it doesn't stop anyone from typing "gmail.com" in the location bar and accessing Gmail if you are still logged. If you are using a shared computer, make sure that you log-out from all your services before handling the computer to somebody else.

Let me know if this clarifies the situation.

Ibai

You can also clear the cookies from the Google (Gmail) site to make sure that you aren't remembered anymore.

• https://support.mozilla.org/kb/Clear+Recent+History
• https://support.mozilla.org/kb/Deleting+cookies

yeah, no answers really hit the point though. where is the option to remove this function, I dont want it, he dont want it, not really sure the point of it is more than a bookmark - who did this and why?

Hi shouldntreallyhavetodothis, I don't know who decided to add page thumbnails into the new tab. Is that important to find out?

If you don't like having thumbnails of frequently/recently used pages in your new tabs, you can switch back to having a completely blank tab. It's a fairly quick change in the about:config preferences editor. The steps are listed in this article:

New Tab Page > How do I turn the new tab page off?.

Firefox 15 and later will have a hidden pref (browser.pageThumbs.enabled) to disable the thumbnails.
In Firefox 16 thumbnail storage will change and the name of the hidden pref will also change in that version to browser.pagethumbnails.capturing_disabled (see resource:///modules/PageThumbs.jsm)

The above answers are not true, I found this out the hard way. Logging out of Gmail does NOT prevent people from being able to click open your account from a new tab page. This is ridiculous! Doesn't anyone test this stuff before instituting changes? I want to go back to Firefox 12!

Hi Foxo, if you log out of Gmail, and you had Firefox save your password, then a page thumbnail, or a bookmark, or typing gmail.com in the location bar all should take you back into Gmail. On your system, can you only get back in using the page thumbnail?

To prevent others from using your saved passwords to log in to sites, set a master password. This article has more information: Use a Primary Password to protect stored logins and passwords.

Thanks, Jsher2000. On my Firefox options, "remember passwords for sites" is not activated, but it still lets me (or anyone else in the room) get back into my gmail account, even though I logged out of gmail and even though I use a gmail verification system. I'm appalled at how these sorts of security concerns get brushed aside in order to accommodate the all-powerful need for some people to have their convenient little history chart.

Can't Firefox make an exception on their history list for password protected sites? Do they not realize that not everyone always has their own computer at work? I'm very disappointed in this.

As for the master password, how does Firefox know which master password belongs to which user if several people are sharing a workstation? They don't explain that in the page you showed.

Foxo,

Shared computers should have separate logon user accounts, or should be setup to clear browser history as Firefox is being closed - just basic privacy precautions.

On my Firefox options, "remember passwords for sites" is not activated, but it still lets me (or anyone else in the room) get back into my gmail account, even though I logged out of gmail and even though I use a gmail verification system.

Is it possible the password was saved before? You can check for saved passwords here:

(Windows) orange Firefox button or classic Tools menu > Options
(Mac) Firefox > Preferences

On the Security tab, the "Show Saved Passwords" button will show previously saved logons.

If Firefox isn't logging you in, another add-on might be doing it. You could test by starting Firefox in Firefox's Diagnose Firefox issues using Troubleshoot Mode to test using Gmail with your add-ons disabled.

As noted by the-edmeister, people sharing a computer generally create different system-level logins so their personal settings and data are all stored separately.

I am having problems with the tab page too. I am new to Firefox, so I don't know if older versions were better, but I do know I am not going to use a browser that openly and easily shows my personal messages, web purchases, facebook pages, and other private information to anyone who uses my computer, even if I have logged out of these sites. And I should not have to set it to clear my history every time I exit or have separate accounts - I have many reasons to want to be able to check my history and the history of other users on my computer - my children among them. That doesn't mean I want everyone who may casually open a new tab to see all the details of every internet session, but I do need to be able to check it from time to time, to make sure my kids are browsing safely and also to find sites I have visited previously. I am uninstalling Firefox now, but I wanted to put this out there to all the people who are telling Foxo that he is doing it wrong or not logging out - that they don't know what they're talking about. Firefox stinks. Back to Internet Explorer for me.

Just some additional information.

For privacy reasons Firefox will be stopping displaying (by default I assume) thumbnail pictures for HTTPS sites (the S stands for Secure ).

That may ease some users worries. The likes of bank and financial transactions (even this forum) use HTTPS

Further details for anyone interested:

Although I argued the thumbnails could be thought of as a security enhancement, because they remind users what is lying around on the computer, it appears it was already decided these should not display.

Long thread title:
New Tab preview window showing sensitive ecrypted information!

including my post /questions/930009?page=2#answer-348421

Good news, 

it appears this was in fact a regression and if I am reading it correctly has already been fixed in Firefox 15 (Aurora)with a possibility it will go into Firefox 14 (Beta) shortly. So if you want the fix now consider using the Aurora channel.

   http://www.mozilla.org/en-US/firefox/channel/#aurora 

Bug 754608 - [New Tab Page] shows thumbnails from pages with "Cache-Control: no-store", and HTTPS pages when HTTPS disk caching is disabled

And although I did not find a security review, there is a Privacy review

   " Privacy/Reviews/New Tab " https://wiki.mozilla.org/Privacy/Reviews/New_Tab

I really don't understand these complaints, I agree with john99, I wish that they still did show secure website thumbnails. All, literally all clicking on one of those new tab thingies does is go to the url, they're just bookmarks. If clicking on the bookmark for gmail.com shows everyone you know your personal email, well, they probably could've been shown that just as easily without the bookmark. a bookmark does nothing to harm security whatsoever.

yeah it's a bookmark which shows an image, an image that... ALSO WAS AVAILABLE to anyone who wanted to find it, as a part of the cache anyways......