When you use the Save Online option to upload to FlashBack Connect, each movie will be available to anyone that you share the link with to view in their browser.
Although, It is not possible for other users to search for and find your movies, you you can also disable access to the movie via the link for anyone who is not logged into your account:
- Log in https://www.flashbackconnect.com/
- Find the movie on the Movies tab
- Click the 3 dots next to the movie
- Click Sharing…
- Select Private and click OK.