Just today, I get the message every time I open up a tab on Duck Duck Go for my email https://outlook.live.com/mail/0/
I've used this for years. Can't understand the sudden issue. And no, there are no options to make this a safe site. Earlier today was fine.
Screenshot attached.
Expanding on peterweb's post a bit. Your screenshot shows an e-mail that shows as "AD", which may be the reason for it being flagged. Outlook dot com opens without any issues my side on Edge and Opera GX browsers on both Windows 10 and 11. FWIW!! I use Google as my default search engine on both browsers.
SA
Can you try accessing that site with a different browser? If you no longer get the warning, it would appear to be an issue with the DuckDuckGo browser that you can try to address with their support.