Nano Defender (a.k.a. uBlock Protector)

An anti-adblock defuser for Nano Adblocker and uBlock Origin

Installation instructions

Nano Defender can only protect either Nano Adblocker or uBlock Origin, and will prioritize Nano Adblocker.

Note: On Microsoft Edge, Nano Defender only works with Nano Adblocker, due to the low quality of Edge port of uBlock Origin. On Safari, Nano Defender does not work at all, and there is no plan in supporting Safari, due to high cost of developer license of $99 per year.


Step 1. Install Nano Defender.

That is it if you are using Nano Adblocker! If you are using uBlock Origin, then you have a few more steps to follow...


Step 2. Enable Adblock Warning Removal List.

Step 3. Install Nano Defender Integration filter list.

Step 4. Go to uBlock Origin dashboard, select "Settings" tab, check "I am an advanced user", click the gears that shows up, replace "unset" after "userResourcesLocation" by "https://jspenguin.com/NanoAdblocker/AssetsMirror/NanoResources.txt" (without quotes).

Note: If you have another User Resources in use, then you would need to either switch to Nano Adblocker or manually merge resources. It takes an eternity to get any resources into uAssets, I have tried.

Step 5. Install Nano filters.

Step 6. Install Nano filters - Whitelist.

Note: My filter lists are now hosted on my own server after criticism from Raymond Hill. Although the old links will still work if you prefer them.

Note: If you are using uBlock Origin, then you must have a functional Internet connection when you start your browser or touch anything in the dashboard.

Other information

Click on the extension icon for announcements, troubleshooting, FAQ, and known issues.


The onbeforescriptexecute event polyfill still does not work on Firefox and it looks like it is not getting fixed anytime soon, so some rules in Nano Defender will only work on Chromium but not Firefox. Firefox is the first browser to get that event and is also the first one to lose it, how sad.

The biggest problem on Firefox right now is Content Security Policy, but thankfully that is getting fixed soon. I recommend you to block all CSP reports until Firefox got the correct implementation of CSP.

On the flip side, thanks of some extra APIs that Firefox has, some rules only work on Firefox but not Chromium, I guess unless you are willing to jump between the two browsers, you cannot have the best of both worlds.

Source code and license

View on GitHub