Hi, which cookies do you want to clear? ''For the site you are viewing in a tab right now, you can:'' Click the lock icon at the left end of the address bar. After a moment, a "Clear Cookies and Site Data" button should appear at the bottom. Go ahead and click that. Firefox will ask you to confirm; go ahead and confirm. ''For other specific sites:'' Open Settings, go to Privacy & Security, scroll down a bit to the "Cookies and Site Data" section and click the "Manage Data" button. This opens a little dialog that lets you remove cookies and site data for individual sites. Note that this will sign you out of the selected sites. ''For all sites:'' Open Settings, go to Privacy & Security, scroll down a bit to the "Cookies and Site Data" section and click the "Clear Data" button. Note that this will sign you out of all sites. Does that cover what you need? The full article has screenshots, so that might help, too: [[Clear cookies and site data in Firefox]].