All you really need to know
- With content blocking on, you can't support websites you love by allowing their ads to appear or whitelist specific YouTube channels to support your favorite YouTubers.
- You have to pause and unpause AdBlock through Safari's extension preferences, instead of using the AdBlock button on the extensions toolbar.
You can only have 50,000 filter rules in use at one time.
You might be thinking, "50,000 filters, so what? That’s plenty!" Well, not really. Some of the filter lists contain tens of thousand of filter rules! For instance, if you have AdBlock Custom, EasyList, and one or two optional lists turned on, you might have to turn one of them off before you can add a language-specific list. If you see the following error message with Safari Content Blocking on, it means that you have subscribed to too many filter lists: The number of filter list rules exceeds the 50,000 limit, and has been automatically reduced. Please unsubscribe from some filter lists or disable Safari Content Blocking!
- If you want to block ads in Flash videos and games on any site, turn content blocking ON. (Remember, with content blocking OFF AdBlock can only block ads in Flash videos on YouTube.com.)
- If you want to make pages load as fast as possible, turn content blocking ON.
- If you want to support websites you love by whitelisting their ads, turn content blocking OFF.
- If you need to use many filter lists at the same time, turn content blocking OFF.
How to turn content blocking on and off
- On your Mac, you can turn content blocking on and off in AdBlock's options, on the "GENERAL" tab.
- On your iPhone or iPad, it's in Settings > Safari > Content Blockers.
Content blocking gives developers a new way to write Safari extensions that block ads. In our case, it allowed us to rewrite AdBlock to make browsing in Safari faster and to block more ads than ever before.
Safari runs faster
If you're not interested in gory technical details, just say to yourself, "Safari runs faster? Cool!" and skip to the next section. :)
AdBlock blocks more stuff
Before content blocking, we weren’t able to block ads in Flash videos and games unless they were on YouTube.com. With content blocking, now we can. (“You’re welcome.” — Apple) That means you no longer need to sit through ads before your video starts or switch to Chrome to watch videos without ads.
Now, the downside
While content blocking allows us to do some things we weren't able to before, it also removes some functionality you may be used to.
- You can’t whitelist (allow ads to show on) individual pages or domains. That means that if you turn on content blocking, we'll automatically turn off the Acceptable Ads filter list, which whitelists thousands of websites.
- You can’t whitelist specific YouTube channels.
- You can’t turn off whitelisted filters in a filter list.
- You have to enable and disable AdBlock through Safari’s extension preferences rather than on the AdBlock button.
- You can only have up to 50,000 filter rules in use at the same time.
- Not all filters are compatible with content blocking. That means some custom filters may not work properly with content blocking on.
- Power users who write lots of custom whitelist filters may find that some of them don’t work. In that case, they’ll need to turn off content blocking and restart their browser to use the old API. Note, however, that this workaround won’t be available forever, since Apple will likely revoke all access to the old API at some point.
If you prefer to use Safari without content blocking, that's fine! Just turn off that setting to get back the AdBlock experience you're used to.
By the way, if you have an iPhone or iPad...