Previous searches stored in cookies persist on sites, even after clearing cookies.
I have been using firefox in private mode ONLY for months now. My privacy settings were set to "custom" with cross-site cookies blocked, tracking content blocked, cryptominers blocked, fingerprinters blocked, in ALL windows.
I have no history, it's automatically deleted. But I have two problems:
1 - On certain sites, you can guess which, my search history is preserved on the site. When I click the search box, it suggests the many things I've searched previously. This even happens when on VPN. I inspect the element and can trace it to see it is stored in some form of cookies. I clear cookies, reset the browser, and it's STILL there!
2 - I have history disabled for a reason. Yet, I still can click the history tab and see "recently closed tabs". That defeats the purpose of disabling history.
Opaite Mbohovái (2)
Such data isn't stored in a cookie.
Do you have search and form data enabled in "Settings -> Privacy & Security" ?
Note that you also can clear "Form & Search" data via "Clear history when Firefox closes".
It certainly is stored in a cookie, which does not clear when cleared via settings. Image below from inspect element:
