Usually your home page and new tab page get switched after installing an extension. Even if you remove the extension, you still need to reset those settings. Let's try that first. This extension will do that in one step (home page back to Firefox default, new tab page back to Firefox default, search engine back to Firefox default): https://addons.mozilla.org/en-US/firefox/addon/searchreset/ ---- You also should review your extensions in case any of them is an ongoing source of this problem. Try disabling ALL nonessential or unrecognized extensions on the Add-ons page. Either: * Ctrl+Shift+a * orange Firefox button (or Tools menu) > Add-ons In the left column, click Extensions. Then, if in doubt, disable (or Remove). ---- If the problem returns after you exit and restart Firefox, there are a few potential causes for this, but rather than make this post longer than it already is, please give us a report on how far you get with these changes.