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Safari has a built-in ad blocker. Select the Safari menu and make sure "Block Pop-up Windows" is checked.
 
I would recommend Safari Adblock on its own. If you add SafariBlock's subscriptions (based on easylist) to the AdBlock subscription list, you will have the same effect as running both and save CPU power.

Here is the subscription address which SafariBlock uses:

http://easylist.adblockplus.org/adblock_rick752.txt

And here are two extras which I use additionally:
http://easylist.adblockplus.org/abp-tracking-filter.txt
http://easylist.adblockplus.org/easylist-element_rick752.txt

Adding these is simple. Just click on the + button on the Subscription tab of AdBlock's options screen.
 
I would recommend Safari Adblock on its own. If you add SafariBlock's subscriptions (based on easylist) to the AdBlock subscription list, you will have the same effect as running both and save CPU power.
The CPU required is so negligible as to be unmeasurable. You could just as easily add Safari AdBlock's subscriptions to SafariBlock, so it could go either way. If I had to choose just one, though, I'd choose SafariBlock for one reason: Safari AdBlock doesn't have a right-click menu item to block specific ads, like SafariBlock does:

Picture 6.jpg
 
The CPU required is so negligible as to be unmeasurable. You could just as easily add Safari AdBlock's subscriptions to SafariBlock, so it could go either way. If I had to choose just one, though, I'd choose SafariBlock for one reason: Safari AdBlock doesn't have a right-click menu item to block specific ads, like SafariBlock does:


True! The devs need to implement that!
 
The CPU required is so negligible as to be unmeasurable. You could just as easily add Safari AdBlock's subscriptions to SafariBlock, so it could go either way. If I had to choose just one, though, I'd choose SafariBlock for one reason: Safari AdBlock doesn't have a right-click menu item to block specific ads, like SafariBlock does:


Where does your "export to PDF" option come from?
 
I think SafariBlock is better than Safari Ad-Block, simply because the latter kept blocking most online videos (like MP4 or DivX), while the former doesn't.

Also, does anyone else think SafariBlock is better than ADP on FF? From my experience, there are certain sites that when you want to close the tab they will pop up annoying dialogues about "chatting with their agent" etc. On FF, I had to click Esc twice to get rid of them, while on Safari I simply closed the tab without a hitch. I was quite impressed as opposed to the ADP on FF, which didn't seem to really do all that much that people claim...
 
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