Deleting saved passwords and login information is a prudent measure to enhance the security of any online activity involving the sites that login information is used for. However, it is not a critical security step, and generally can be disabled without a significant increase of risk.
To prevent SparkTrust Privacy Cleaner from removing this information in future:
- Open Options.
- Select More Info next to the internet browsing history section.
- Click the + icon besides your browser to expand the category.
- Deselect saved passwords, and any other categories you do not wish to clean.
- Depending on the level of security and the types of information stored on sites you commonly access you may also want to deselect Cookies, Favorites, History (visited sites), and Auto-Complete form data.