Re-captha-version-3-21.top is generally considered to be a potentially unwanted software that can compromise the security and privacy of a user's web browsing experience. While it might not be as malicious as some other types of malware like Trojans or Ransomware, this program is not entirely safe. Its primary objective is to alter browser settings without the user's consent, often leading to unwanted changes in the default search engine, homepage, and new tab settings. These modifications can redirect users to questionable websites, display excessive advertisements, and potentially expose them to phishing or other online threats.