YouTube is one of the last big platforms openly hosting QAnon content after its users were kicked off Facebook and Instagram

• Facebook and Instagram conducted their most comprehensive purge of QAnon accounts to date on Tuesday.
• The sites removed thousands of accounts spreading the groundless conspiracy that President Trump is secretly battling a cabal of child-abusing elites.
• YouTube, though, still hosts thousands of pro-QAnon posts.
• "Videos are central to QAnon as video is the most used medium to circulate QAnon content across digital ecosystems," commented Marc-Andre Argentino, an online extremism expert.
• YouTube has introduced policies meant to limit disinformation, but has only been partially successful in enforcing them.
• In the past, YouTube's algorithms pushed extremist content to thousands of viewers, but the site said it is changing them,

The QAnon conspiracy movement suffered a serious blow on Tuesday, when Facebook and Instagram removed hundreds of the movement's largest pages, accounts, and groups.

The platforms said they would ban QAnon content, expanding a policy that had previously tolerated QAnon posts as long as they were non-violent.

However, the movement still has a home on one of the biggest online platforms: YouTube.

And the conspiracy movement will keep spreading online unless YouTube takes action to remove the videos and channels it hosts promoting the conspiracy, experts say.

The site has long been a hub for the movement, where believers promote their theories to tens of thousands of viewers on YouTube channels.

A YouTube spokesman told Business Insider that it had "removed tens of thousands of Q-related videos, and terminated hundreds of Q-related channels for violating our hate and harassment policies since 2018."

Videos claim to unveil a child-abusing elite than runs the world

QAnon videos on the site explore the movement's groundless belief that an elite network of child abusers secretly manipulates world events.

They are widely shared and discussed in private groups on social media, and with thousands of others on platforms like Twitter. The messaging site is another major platform where efforts to limit the conspiracy theory have had only limited success, reported The Washington Post.

The movement, which claims President Donald Trump is secretly working to dismantle the cabal, has been tied to several violent crimes.

The FBI in a memo in 2017 described it as a potential domestic terror threat. Several Republican congressional candidates have openly embraced the conspiracy theory, and in controversial remarks at a press briefing in August Trump said he welcomed its support.

Cursory searches by Business Insider on Tuesday found it hosts hundreds of videos promoting the QAnon conspiracy theory, and that pro-QAnon channels have tens of thousands of subscribers.

A Pew Research study in September found that 5% of the 100 most viewed independent news channels on the site mentioned QAnon, while 2% were primarily focused on the conspiracy.

"YouTube has yet to take action against QAnon. YouTube Videos are central to QAnon as video is the most used medium to circulate QAnon content across digital ecosystems," tweeted Marc Andre Argentino, a researcher at Canada's Concordia University who specialises in online extremism.

"As long as QAnon content still has a home on YouTube, we will continue to see their content on all social media platforms, and there is not much Facebook can do about that. This will require a multi-platform effort."

In a statement to Business Insider, YouTube spokesman Alex Joseph oushed back against the claim that the site had taken insufficient action to limit the spread of QAnon videos.

"We've removed tens of thousands of Q-related videos, and terminated hundreds of Q-related channels for violating our hate and harassment policies since 2018. Additionally, we surface videos from authoritative sources for Q-related searches and provide context by linking to third-party sources in our information panels," he said. "

In early 2019, we also began updating our systems to reduce recommendations of borderline content, including Q-related conspiracy theories, and have seen the number of views that come from recommendations to prominent Q-channels (those that have not already been terminated for repeated violations) drop by over 80%."

Algorithms pushing Q

QAnon believers migrated to mainstream platforms like YouTube after the movement emerged on the messaging boards 4Chan and 8Chan in 2017.

They soon began making videos to explain and spread their beliefs and pore over clues and messages they believe are being leaked by government sources. (There is nothing to suggest any of these messages really come from within the government.)

YouTube has introduced measures in recent years to clamp down on videos promoting disinformation more broadly. In January 2019 it said it would limit the spread of videos "that could misinform users in harmful ways."

But the site has been accused of taking a lax approach to fulfilling the pledge, as it seeks to maintain a balance between ensuring freedom of speech, and not allowing dangerous conspiracy theories to spread unchecked.

Its algorithms have been found to boost white nationalist and QAnon material in the past, giving users automatic suggestions to watch more and more extreme content.

In 2019 Business Insider found thousands of videos on the site pushing a type of toxic bleach as a cure for a raft of incurable illnesses that were surfacing as top results for searches on general health topics.

The site has committed to changing its algorithms to demote conspiracy theory videos and favor authentic news reports more visible. It has also removed advertisements on videos promoting anti-vaccination misinformation.

However experts at the University of Berkeley, California, in March found its efforts to prevent conspiracy theory videos being pushed to thousands had been a mixed success.