Facebook is ending a feature that allowed users to hide from the social network's billion-plus members.

The feature, akin to Harry Potter's invisibility cloak, will be removed, meaning that someone looking for another Facebook user can more easily find that person.

"The setting was created when Facebook was a simple directory of profiles and it was very limited," said Facebook's chief privacy officer, Michael Richter.

The setting made Facebook search "feel broken at times," Richter added in a company blog Thursday.

"For example, people told us that they found it confusing when they tried looking for someone who they knew personally and couldn't find them in search results, or when two people were in a Facebook Group and then couldn't find each other through search."

Facebook announced last year that it was ending this feature for new users, but allowed a transition for a "small percentage" of users who had that feature enabled.

Richter said the change should not have an impact on overall privacy.

"Whether you've been using the setting or not, the best way to control what people can find about you on Facebook is to choose who can see the individual things you share," he said.

Facebook, which has been under scrutiny by privacy advocates, recently revamped its search functions to include a so-called "graph search" that allows users to search through a wide range of posts on the world's biggest social network.

In a separate development, Google announced that it was following Facebook's lead for users' pictures and endorsements to appear in product ads.

The change will take effect November 11, Google said in its updated terms of service.

"We want to give you -- and your friends and connections -- the most useful information," the document said.

"Recommendations from people you know can really help. So your friends, family and others may see your profile name and photo, and content like the reviews you share or the ads you (liked)."

Google said users can opt out of this feature, however, and added that it will not use endorsements from users under 18.

But the Electronic Privacy Information Center said Google's shift may violate a 2011 agreement with the Federal Trade Commission because it would employ photos without user consent.

A statement from the group said the order "prohibits Google from making misrepresentations and requires the company to obtain user consent before disclosing information to third parties."

Greg Sterling, analyst with Sterling Market Intelligence, warned that the shift may backfire on Google.

"Shared endorsements could boost display ad performance but might have the unintended consequence of discouraging reviews," Sterling said.

Danny Sullivan of Search Engine Land said Google users' pictures had already appeared in ads, but that the new policy expands the practice by allowing endorsements from "social actions" in addition to Google's +1, the equivalent of Facebook's "like" button.

"Obviously, look closely at any type of social activity you do," Sullivan said in a blog post.

"If it's tagged as public, then what you do is fodder for shared endorsements within ads, unless you opt out of ad use and also do limited sharing for non-ad use, if allowed."