Users who have upgraded to MacOS Mojave and Safari 12 may be startled to see the following warning when they try to install AdBlock from our website: "Safari no longer supports the unsafe extension "AdBlock."
AdBlock is still safe to use
First, AdBlock hasn't suddenly become unsafe to use. The warning is Apple's way of notifying users that an extension is built on an older way of developing and distributing Safari extensions that's being phased out. These legacy extensions such as AdBlock run only inside Safari and can be installed either from the developer's website or the Safari Extensions Gallery. With MacOS Mojave and Safari 12, Apple's preferred development and distribution platform is "Safari App Extensions"—native Mac applications that users install exclusively from the Mac App Store.
What does the move to Safari App Extensions mean for me?
As with most big changes, there is good news and bad news.
The good news for users is that Safari App Extensions are faster, more secure, and lighter on computer memory and processor performance than legacy extensions are.
The bad news comes in three parts. First, legacy extensions that were installed directly from the developer's website will be disabled the first time you run Safari 12. (There is a way to install them anyway, but it is not for the faint of heart.)
Second, even legacy extensions you install from the Safari Extensions Gallery will eventually stop working, probably sometime in 2019.
Finally, converting legacy extensions to the new Safari App Extensions platform won't be easy, for a variety of technical reasons we won't get into. Some developers, particularly developers of free extensions, may decide it just isn't worth the effort. You may find some of your favorite extensions don't survive the transition.
How will AdBlock be affected?
AdBlock for Safari is not going away. We are making the move to the Safari App Extensions platform in two steps to minimize disruption to our users.
Step 1: Make Content Blocking the only way to block ads in the current extension
In the current version of AdBlock, users may choose to block ads the way we used to, before Apple introduced Content Blocking with Safari 9, or the way that uses Content Blocking. The Content Blocking method is more efficient at blocking more kinds of ads, but it imposes a few limitations the old way doesn't.
Along with removing support for the old way to develop extensions, Apple is also phasing out the old way of blocking ads. (See the Safari Extensions section here for more technical detail: https://developer.apple.com/safari/whats-new/). We’re working on a release that will exclusively use the Content Blocking method. Learn more about what's different with Safari Content Blocking in AdBlock.
Step 2: Create a new AdBlock App Extension
At the same time, we are working on an App Extension that will ultimately become a brand-new AdBlock for Safari. We plan to have it ready and available in the Mac App Store in the fall.
Can I still use the current AdBlock with Safari 12?
If you installed AdBlock from our website or sideloaded the .safariextz file, you will not be able to use AdBlock after you upgrade to Safari 12. Please install it from the Safari Extensions Gallery instead. Just click through the warnings you'll receive during installation.
If you installed AdBlock from the Safari Extensions Gallery, you can continue to use it after upgrading to Safari 12. It will be disabled the first time you launch Safari. You can enable it again in Safari Extensions preferences.
The current version of AdBlock will stay around as long as the Safari Extensions Gallery does for compatibility with older versions of Safari. Please note, however, that we may decide to stop developing new features for it at some point.