In Firefox 13 and later versions, nine different websites thumbnails are displayed in 3×3 grids when you open a new tab. This feature, while useful, displays your browsing history to anyone working on your computer. If you are not comfortable with this open display of your browsing history, it is best that you disable this feature. Here’s how you can do it.
Method 1 – Remove the thumbnails temporarily
This method does not offer a permanent fix. But it is very easy to perform, and so is worth discussing here.
Open a new tab and click the symbol with 9 little squares (located in the upper right corner) to remove the thumbnails. The thumbnails now will no longer automatically appear every time a new tab is opened. To get the thumbnails back, simply click the symbol again.
Method 2 – Remove the thumbnails permanently
This method removes the thumbnails permanently.
In Firefox’s new tab, type about:config to access the browser’s configuration settings. Locate the browser.newtab.url entry (it is displayed under the search field), and double-click it. This entry, by default, is configured to about:newtab. Change this to about:blank and save your changes.
Thumbnails, which allow others to see your browsing history, are a privacy rather than a security issue. Malware programs, which can also disclose information present on your pc to others, on the other hand, are very dangerous. It is important that you keep yourself protected against such programs. The best way to do this is by using an advanced antivirus tool.