After testing dozens of scripts and websites, these are the most reliable free solutions. Warning: These methods exist in a legal gray area. Use them at your own risk.
There are dedicated extensions like "Udocz Free Download" or "Academic Downloader" available on third-party sites (not the official Chrome Web Store, as Google removes them). Udocz Downloader BEST Free
Udocz allows free users to view the first few pages of most documents. After testing dozens of scripts and websites, these