This extension do not collection anything from your browser / computer. And even do not trigger a single network request it self. The site named `6905b838-e843-4ee3-9df0-b4c79673b21c.invalid` is literally _invalid_ and no one may hold that site. Your search words will only be sent to the search engine you configured in the extension but not any other servers. Extension come up by some default search engines to make it easy to use. The default search engine list is decided by your language settings, and the list is based on Firefox built-in search engines. If you dislike some search engine given in the list, you may just remove it in extension settings by one click.