There is no "Settings, Browsing". And in "Tabs and Browsing" there siu bnithing abiut controlling popups

Firefox itself does not block YouTube ads by default. What people are usually referring to is using an extension like uBlock Origin. Try this: * Open Firefox. * Go to Add-ons and Themes (or press Ctrl + Shift + A). * Search for uBlock Origin and install the one from the official developer. * Restart Firefox and test YouTube again. The "Settings → Browsing" option you were told about is probably from an older Firefox version or a different browser. Firefox's built-in popup protection mainly handles website popups, not video ads. If you already installed an ad blocker and it isn't working, check that the extension is enabled and that Firefox hasn't blocked its permissions. YouTube changes its ad system often, so keeping the extension updated is important