Firefox blocks pop-ups by default, and you can turn that off in Settings

Firefox comes with a built-in pop-up blocker that stops most pop-up windows from opening. If a website you trust needs pop-ups to work properly — like a banking site that opens statements in a new window, or a tool that displays results in a pop-up — you can disable the blocker entirely or create an exception for just that one site.

The fastest route is to turn off the blocker in Firefox Settings. If you only want to allow pop-ups on one specific website, you can add that site to an exceptions list instead, which keeps the blocker active everywhere else. This approach gives you control over which sites can open pop-ups while protecting you from unwanted advertisements on other websites.

Key Takeaways

  • Firefox's pop-up blocker is controlled in Settings under the Privacy & Security tab, in the Permissions section.
  • You can disable the blocker completely, or add individual websites to an exceptions list so they can open pop-ups while other sites remain blocked.
  • If Firefox blocks a pop-up you wanted to see, a notification bar appears at the top of the page with an option to allow it just that once.
  • Some websites require pop-ups to function, so you may need to disable the blocker or add an exception before certain features work.

Disable the pop-up blocker completely

Open Firefox and click the menu button (three horizontal lines) in the top right corner. Select Settings from the dropdown menu. This opens the Firefox Settings page where you can control how the browser behaves.

On the left side of the Settings page, click Privacy & Security. Scroll down until you see the Permissions section. You will see a checkbox next to "Block pop-up windows" — uncheck this box to turn off the blocker entirely. Firefox will now allow all pop-ups from all websites. If you change your mind later, you can return to this same checkbox and turn the blocker back on.

Allow pop-ups on one website only

If you want to keep the blocker on for most sites but allow pop-ups on one specific website, you can add that site to an exceptions list. Go to Settings > Privacy & Security and find the Permissions section again. This method is safer than disabling the blocker completely because it protects you from pop-up advertisements on other sites while still letting your trusted website function properly.

Next to "Block pop-up windows," click the Exceptions button. A small window will open. Type the website address (for example, www.yourbank.com) into the text field and click Allow. That website can now open pop-ups, but Firefox will continue blocking them everywhere else. Click Save Changes when you are done. You can add as many websites as you need to this list.

Allow a pop-up that Firefox just blocked

When Firefox blocks a pop-up, a notification bar appears at the top of the page. The bar says "Firefox blocked a pop-up window" and includes a button labeled Show or Allow. Click this button to let that single pop-up through without changing any settings. This is a temporary permission that applies only to that one pop-up on that one visit.

This is useful if you only need pop-ups from a site once in a while. You do not have to change your settings — just allow the pop-up when you need it, and the blocker stays on for everything else. The next time you visit that website, Firefox will block pop-ups again unless you add the site to your exceptions list.

Check and manage your exceptions list

Go to Settings > Privacy & Security and click Exceptions next to "Block pop-up windows." A list of all websites you have added will appear. You can review which sites are currently allowed to open pop-ups and make changes whenever you want.

If you want to remove a site from the list, select it and click Remove. The blocker will then apply to that site again. This is helpful if you added a website to the exceptions list but no longer trust it, or if you realize you do not actually need pop-ups from that site. You can also remove all exceptions at once by clicking Remove All if you decide to start fresh.

Troubleshooting: Pop-ups still do not work

If you have disabled the blocker but pop-ups still are not appearing, the problem may be elsewhere. Check whether your operating system (Windows, Mac, or Linux) has its own pop-up blocker turned on, or whether another security program on your computer is blocking them. Some antivirus software and security tools include their own pop-up blockers that work independently of Firefox.

Some websites also use different methods to open windows that Firefox's blocker does not catch, or they may require you to change other browser settings. If a specific website's pop-ups are not working, try adding it to the exceptions list first — if that does not help, the issue is likely on the website's side or with another program on your computer. You can also try clearing your Firefox cache and cookies for that website, as outdated stored data sometimes interferes with how websites function.

Frequently Asked Questions

Why does Firefox block pop-ups?

Most pop-ups are advertisements, and blocking them improves your browsing experience and reduces distractions. However, some legitimate websites use pop-ups for important functions like displaying documents or opening login windows, which is why Firefox lets you turn the blocker off when you need to.

Will disabling the pop-up blocker slow down Firefox?

No, turning off the blocker will not affect Firefox's speed. You may see more pop-ups on websites, but the browser itself will run at the same pace.

Can I disable the pop-up blocker for just one tab?

No, the pop-up blocker setting applies to all tabs and windows in Firefox. You can only disable it completely or add specific websites to an exceptions list. If you need pop-ups on just one site, adding that site to exceptions is the best approach.

What if I accidentally allow pop-ups on a website I do not trust?

Go back to Settings > Privacy & Security > Exceptions next to "Block pop-up windows," find the website in the list, select it, and click Remove. The blocker will apply to that site again.

Do I need to restart Firefox after changing pop-up blocker settings?

No, Firefox applies pop-up blocker changes immediately. You do not need to close and reopen the browser for the new settings to take effect.