If you look in the faq at the bottom of the page, you'll see how it works. Here's what it says

How Do I Flag Content I Don't Like? If you see content you don't like, you can click the ... next to the post or comment to flag it. This is a form of negative feedback that helps Stacker News decide which content should be visible on the site.

It costs 1 sat to flag content, and doing so doesn't affect your trust or the trust of the user who posted the content. Instead, it simply lowers the visibility of the specific item for all users on Tenderfoot mode.

If an item gets flagged by users with enough combined trust, it is outlawed and hidden from view for users on Tenderfoot mode. If you wish to see this flagged content without any modifications, you can enable Wild West mode in your settings.

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What Is Tenderfoot Mode? Tenderfoot mode hides or lowers the visibility of flagged content on Stacker News. This is the default setting for all users.

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What Is Wild West Mode? Wild West mode allows you to see all content on Stacker News, including content that has been flagged by users.

This unfiltered view doesn't modify the visibility of items on Stacker News based on negative feedback from users.

You can enable Wild West mode in your settings panel.

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