Social media apps constantly feed users content that they’ll supposedly enjoy based on algorithms that mine their past scrolling habits.
Clicking a like or dislike button on a post, many people assume, factors into the formula. The thinking is that showing a preference, or not, provides some control over what they’ll see on that service in the future.
But a new study published today shows that you have far less control than you might expect.
Nonprofit organization Mozilla released what it calls “the largest experimental audit of YouTube by independent researchers,” finding that YouTube’s content controls are largely ineffective.
To conduct the study, Mozilla recruited nearly 23,000 participants and analyzed nearly 568 million videos. The organization, which owns a subsidiary that manages and develops the Firefox internet browser, also surveyed over 2,700 people about their experiences with the platform.
The study focused on claims by YouTube owner Alphabet that users can exercise some control over the content they see.
“There are several ways to influence these recommendations and search results,” reads a page in the YouTube help center. “You can remove specific videos from your watch history and searches from your search history. You can also pause your watch and search history, or start fresh by clearing your watch and search history.”
But through its research, Mozilla found that these actions do not have a significant impact on the algorithms that ultimately present users with suggested content.
Clicking “don’t recommend channel” was the most successful of those tools, with a 43% success rate, according to the study. Clicking “not interested” on a video was only 11% effective, while disliking it was 12% effective. Removing a video from one’s watch history was only 29% effective.
Alphabet did not respond to Fortune’s request for comment.
Mozilla, founded in 2003, bills itself as a platform “dedicated to putting you in control of your online experience” and promoting the internet as a public good.
“Our main recommendation is that YouTube should enable people to shape what they see, wrote the organization in its report. “People should be provided with clear information about the steps they can take to influence their recommendations, and should be empowered to use those tools.”
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