When you install AdBlock Premium for the first time, Chrome will show you a notification like this:
About the permissions AdBlock Premium requests
Lifehacker has a nice article on what browser permissions really mean and how much you should worry about giving them. Here's what they mean when you use AdBlock Premium.
"Read and change all your data on the websites you visit"
Ad blockers work by 1) blocking a web page's requests to download ads from the servers that host them and 2) hiding any ads that can't be blocked. (For details, please see our "Ad Blocking 101" post on AdBlock's Blog.) To do that, the extension needs to:
- See every page you open so that AdBlock Premium can work on every page you visit. This also means that AdBlock Premium knows the URL (Internet address) of every page you visit.
- See all the data on the page to find any unblocked ads among the other content. This also means that AdBlock Premium can see any forms you submit and your browsing history on that tab.
It's important to know that just because AdBlock Premium can see everything on a web page, it doesn't mean it actually does read everything or does anything with it. The extension does not record your browsing history, capture your passwords or bank account numbers, or secretly change data you submit on a web form.
AdBlock Premium needs to send data about a page back to our servers, where some of the extension's functionality is hosted.
"Communicate with cooperating websites"
The "cooperating website" is our own, getadblock.com. We need your permission to enable our website and the extension to share information. The post-installation page on our website sends information to the extension to help us market AdBlock Premium more effectively. The post-payment page on our website tells the extension when your license is activated.
"Manage your apps, extensions, and themes"
This permission is requested later, the first time you report an ad or a bug. It allows Chrome to share information with us about other extensions you have installed.
About the information we collect
All that said, we want you to know that we do collect some information about your browser and AdBlock Premium, not about you personally.
We get statistics from Google Analytics and the AdBlock Premium extension that tell us, for example, the language your browser is set to and the country you're in. None of the information that we collect is personally identifiable. If you want to prevent us from seeing this information anyway, you can upgrade to AdBlock Premium Gold and subscribe to the EasyPrivacy filter list, which prevents all forms of browser tracking.
Troubleshooting information you send us
If you provide debugging information as part of troubleshooting an issue, AdBlock Premium tells us your operating system version, which browser you're using and its version, how long it's been since you installed AdBlock Premium, which version of AdBlock Premium you're using, which options you have set, which filter lists you're subscribed to, any custom filters you've added, and (if you give us permission to collect it) which extensions you have installed and whether they're enabled.
You can read this information yourself to see what you're giving us. Open AdBlock Premium's options and on the SUPPORT tab, click here in the sentence "Have our team requested some debug info? Click here for that!"
You're right to be wary, absolutely. You should never install extensions that ask for more permissions than you are comfortable with unless you trust the developer. AdBlock is the most popular extension for Chrome and Safari, in large part because we care about our users. We hope you'll trust us. If you're ever concerned, just ask us! :)
By the way, if we ever release a new feature that requires additional permissions, your browser will alert you to that fact. Some browsers such as Chrome even disable extensions that request additional permissions. In those cases you must specifically grant the new permission by re-enabling the extension.