How to find Chrome extensions that inject ads into any webpage I browse?

Depending on your JavaScript knowledge, you can check out the scripts that can manipulate websites you visit.

  1. Press F12 to open the Developer Tools. Alternatively, open the Developer Tools from the "hamburger menu":

    enter image description here

  2. On the Sources tab, select the Content scripts tab. You should see a list of all your extensions that load content script.

    enter image description here

    "Content script" is the term that is used for scripts that are running in the context of the website you're visiting. These scripts have the ability to manipulate web content in any way they want.

  3. You can now inspect those scripts and see how they're messing with your page.

    Hint: In case they're using minified sources, enable the code beautifier:

    enter image description here

My way is easier, since you don't have to examine extensions like AdBlock which don't add elements to your page :)

Also, If you aren't a tech-savvy, go to the bottom: there's any solution that may work for you...

  1. Open the Developer Tools

    Developer tools

  2. Open the Developer Tools in a new window and reduce the window to icon DockDock

  3. Browse the web and wait for the Ads to appear. In this case I'm using an extension which replaces ads with cats pictures

    cat picture

  4. Go to the Network tab, and look for the initiator column. Usually it's called something like content script.js. Click it and that's the content script that messed up your page.


  5. If from taking a look at the code you can't guess which extension is, you can go to Sources tab, click on Content Scripts and look for the extension with a *.js file named like the one we found at point 4.


Easier method (may be less effective)

  1. Go to the installed extensions page

    extension page

  2. For each extension, click on Details


  3. If the Ads started popping up just recently, look for when it was updated. Chrome extensions update by themselves. This may help you if you started seeing ads today and casually the extension was updated today

    update date

  4. Last but not least, look at the reviews, preferably ordered by Recent. If you see somenthing like this, you may have found the culprit.

    User reviews

Disable all chrome extensions, see if the problem stops. Enable each extension one by one. When the issue reappear, you have found the culprit.