This is the most reliable "old school" method that still works in 2025. It bypasses the standard mobile and desktop interface by forcing Facebook into its basic HTML mode. Copy the Link
Here’s a on what you can do:
Click on the address bar. Change the www or web in the URL to mbasic . Download Facebook Private Profile Picture
Downloading and using someone’s private profile picture without permission may violate: This is the most reliable "old school" method
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