Update November 25, 2017:
This week, a broken filter in one of the filter lists AdBlock uses, the Adblock Warning Removal list, caused this notification to appear constantly. The list authors (who are not affiliated with AdBlock) fixed the filter and updated the list. AdBlock received the update automatically.
If you see the "Hide targeted messages" notification and it's not appearing constantly, this is expected behavior. Please keep reading!
You visit a website and a little box pops up that looks like the picture below.
What does it mean?
This site has been known to show targeted messages to AdBlock users. The current website is on a list of sites that are known to use obtrusive messages to ask visitors to turn off AdBlock. "Obtrusive" messages are those that pop up and take over the entire screen, such as the one on Forbes.com. Sites that show unobtrusive requests, such as Theguardian.com, are not put on the list.
Do you want AdBlock to hide targeted messages? Do you want to enable a filter list in AdBlock that can prevent these websites from showing you obtrusive requests to turn off AdBlock?
The filter list is called the Adblock Warning Removal list. Note the lower-case "b" in "Adblock." This filter list removes warnings about ad blockers in general, not AdBlock specifically. Subscribing to that filter list is one technique to get to content on anti-adblocking sites.
The notification should only appear the first time you visit a website that's on the Adblock Warning Removal list when the list is disabled.
What can I do about it?
Click Yes to enable the Adblock Warning Removal list. Click No to leave the filter list disabled. Either way, you shouldn't see the message again. Making a choice tells AdBlock it doesn't need to show you the notiication anymore.
If you close the notification without selecting either Yes or No, it will return the next time you visit a website that's included in the Adblock Warning Removal list.
The website you are currently visiting when the notification appears is the one the notification refers to. However, the choice you make applies to all websites you visit from that point onward. The setting is not specific to any one website. All the notification does is make it easy to either disable or enable the Adblock Warning Removal list. You can easily do this manually on the FILTER LISTS tab in AdBlock's options.
I clicked "Yes" but I changed my mind
If you clicked Yes but now you want to allow sites to show you requests to turn off AdBlock, whether they are obtrusive or not, disable the Adblock Warning Removal list in AdBlock's options, FILTER LISTS tab.
I clicked "No" but I changed my mind
If you clicked No but now you're tired of seeing obtrusive requests to turn off AdBlock, enable the Adblock Warning Removal list in AdBlock's options, FILTER LISTS tab.
Please note that the Adblock Warning Removal list may not be able to prevent all websites from showing requests to turn off AdBlock. If a request is not blocked, and the site doesn't allow you to view its contents with AdBlock running, please see this article for suggestions.