This wikiHow teaches you how to prevent pop-up ads from appearing in the Firefox browser on both desktop and mobile platforms. While you can't 100% prevent pop-up windows in Firefox and other browsers, you can reduce the number of pop-ups that appear (to none at all) using Firefox's built-in pop-up blocker feature. You can also use a Firefox extension called Adblock Plus to block more annoying ads on desktop Firefox. Firefox mobile users can download the free Firefox Focus app to browse the internet without being distracted by ads.
Step
Method 1 of 5: Using Firefox Settings on a Desktop Computer
Step 1. Open Firefox
This browser icon looks like an orange fox surrounding a blue globe.
Step 2. Click
It's in the top-right corner of the page. A pop-out window will be displayed.
Step 3. Click Options
It's in the pop-out window.
On a Mac computer, click “ Preferences ”.
Step 4. Click Privacy & Security
This tab is at the far left of the page.
Step 5. Scroll to the "Permissions" section
This segment is at the bottom of the page.
Step 6. Check the box "Block pop-up windows"
This box is at the bottom of the "Permissions" section. With this option, Firefox will block pop-up windows (including ads) from appearing.
If the box is checked from the start, Firefox is already blocking pop-up windows
Method 2 of 5: Using Firefox Settings on iPhone
Step 1. Open Firefox
Tap the Firefox browser icon, which looks like an orange fox circling a blue globe.
Step 2. Touch
It's in the lower-right corner of the screen. Once touched, a pop-up window will load.
Step 3. Touch Settings
It's at the bottom of the pop-up window. After that, the settings window or “Settings” will be displayed.
Step 4. Touch the white "Block Pop-up Windows" switch
The color of the switch will turn blue indicating that from now on, pop-up ads are blocked in Firefox on your iPhone.
If the switch is blue in the first place, the pop-up has been blocked
Method 3 of 5: Using Firefox Settings on Android Device
Step 1. Open Firefox
Tap the Firefox browser icon, which looks like an orange fox circling a blue globe.
Step 2. Touch the address bar
This bar is at the top of the screen.
You may need to swipe up on the screen first to display the bar
Step 3. Visit the system settings page
Type about:config into the address bar and tap the "Search" button.
Step 4. Touch the search bar
It's in the upper-right corner of the screen.
Step 5. Look for the pop-up blocker option
Type in dom.disable_open_during_load and hit the " Search " button.
Step 6. Make sure this option is labeled "false" below it
If you see the label " true " under the text “ dom.disable_open_during_load ”, Firefox has blocked pop-ups.
Step 7. Enable pop-up blocker
Touch " dom.disable_open_during_load, then select " Toggle ”.
Step 8. Restart Firefox
Close and reopen Firefox. Now, Firefox will block the ads that appear on the internet, including pop-ups.
Method 4 of 5: Using Adblock Plus
Step 1. Open Firefox on the computer
This browser icon looks like an orange fox surrounding a blue globe.
Unfortunately, you can't install Adblock Plus for use on the iPhone or Android versions of Firefox
Step 2. Go to the Adblock Plus extension page
On this page, you can download Adblock Plus.
Step 3. Click Add to Firefox
It's a blue button in the middle of the page.
Step 4. Click Add when prompted
This button appears at the top of the window. After that, Adblock Plus will be installed into Firefox.
Step 5. Click the Adblock Plus icon
The icon looks like a stop sign with a white “ABP” in the middle. You'll find this icon in the upper-right corner of the Firefox window. Once clicked, a drop-down menu will appear.
Step 6. Click Options
This option is at the bottom of the drop-down menu. The Adblock Plus page will open.
Step 7. Uncheck the "Allow Acceptable Ads" box
This box is in the " ACCEPTABLE ADS " section of the page.
Step 8. Browse the internet without annoying pop-ups
Once Adblock Plus is installed, you can avoid the appearance of various ads (both in the form of pop-ups and otherwise) on the Firefox desktop browser.
- You may still see the occasional ad, and some websites require you to disable an ad blocker so you can view the content.
- To disable Adblock Plus, click the add-ons icon (you may need to click the “ ☰ ” in the upper right corner of the browser window to see the icon), then select “ Enabled on this site ”.
Method 5 of 5: Using Firefox Focus
Step 1. Understand how to use Firefox Focus
Firefox Focus is a free version of Firefox for iPhone and Android smartphones. This browser has a built-in ad-blocker feature that can prevent the appearance of most pop-ups and various types of annoying ads.
Firefox Focus is not available for Windows and Mac computers
Step 2. Install the Firefox Focus app
To install it, go to
App Store (iPhone) or
Play Store (Android), then follow these steps:
- iPhone - Touch “ Search ”, select search bar, type firefox focus, touch “ Search ", choose " GET ” to the right of the Firefox Focus icon, and scan for Touch ID or enter your Apple ID when prompted.
- Android - Touch the search bar, type firefox focus, touch the " Search " icon, and tap “ INSTALL ” under the Firefox Focus heading.
Step 3. Open Firefox Focus
After the browser has finished installing, touch the “ OPEN ” in the app store window or select the purple and white Firefox Focus icon.
Step 4. Touch Skip
It's in the top-left corner of the screen.
Step 5. Browse the internet as usual
Since Firefox Focus includes and activates an intensive ad blocker automatically, you can browse the internet right away without having to worry about annoying pop-ups appearing.
