Hi, open the 3-bar menu and look for Options. If you can't see it, please see - Customize Firefox controls, buttons and toolbars. If still not visible, click on Restore Defaults as shown in the article.

Alternatively, to bring up the menu bar (with Options under the Tools tab) temporarily, press Alt. If you would like it to remain there all the time, right click in the tab bar (but not on a tab) and tick/check Menu Bar.

Are you using the default about:newtab page as your new tab page, or did you change it to something else?

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Try the Firefox Safe Mode to see if the problem goes away. Firefox SafeMode is a troubleshooting mode that temporarily turns off hardware acceleration, resets some settings, and disables add-ons (extensions and themes).

If Firefox is open, you can restart in Firefox Safe Mode from the Help menu:

• Click the menu button , click Help and select Restart with Add-ons Disabled.

If Firefox is not running, you can start Firefox in Safe Mode as follows:

• On Windows: Hold the Shift key when you open the Firefox desktop or Start menu shortcut.
• On Mac: Hold the option key while starting Firefox.
• On Linux: Quit Firefox, go to your Terminal and run firefox -safe-mode
  (you may need to specify the Firefox installation path e.g. /usr/lib/firefox)

When the Firefox Safe Mode window appears, select "Start in Safe Mode".

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, theme, or hardware acceleration. Please follow the steps in the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article to find the cause.

To exit Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

When you figure out what's causing your issues, please let us know. It might help others with the same problem.

In case you need more reading, here's how you can change your new tab page:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful.

(2) In the search box above the list, type or paste newtab and pause while the list is filtered

(3) Double-click the browser.newtab.url preference and enter your preferred page:

• Page thumbnails (default) => about:newtab
• Blank tab => about:blank
• Built-in Firefox home page => about:home
• Any other page => full URL to the page

Press Ctrl+t to open a new tab and verify that it worked. Fixed?

If problems persist, some potential diagnoses and remedies:

If Firefox won't let you edit this setting: you may have something called SearchProtect on your system. This needs to be removed from the Windows Control Panel. If the status says "locked" we will need to help you investigate an "autoconfig" file.

If Firefox lets you save your change but ignores it: one of your extensions may be overriding it. You can review, disable, and/or remove extensions on the add-ons page. Either:

• Ctrl+Shift+a (Mac: Command+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Extensions. Then cast a critical eye over the list on the right and disable (or remove) anything unknown.

If the change works during your session, but at the next startup is back to the unwanted page: you might have a user.js file in your personal Firefox settings folder (your Firefox profile folder). This article describes how to track down and remove the file: How to fix preferences that won't save.

Any luck?