⚠️ UPDATE ⚠️
I discovered that it seems to work with https://httpbin.org/basic-auth/foo/bar but not with http://212.227.48.141/
Maybe it is because of https? Any comments on this issue are welcome!
When you open a website that has a native login prompt (with .htaccess and .htpasswd) it does not show up and the website just says „Unauthorized“.
I tested it with Safari and the Orion browser, both on Mac and Mobile (iPad). You can test it yourself using the following urls:
See my update on top!
In Safari, it shows a popup to enter login credentials: 
In Orion browser, nothing pops up and the website just says „Unauthorized“: 
System Information:
Orion version (Mobile): 1.3.18 (6) (WebKit 8621.1.10.20.6)
Orion version (Desktop): Version 0.99.131.0.1-beta (WebKit 621.1.2.111.4)
iPadOS version: 18.4 Developer Beta 2
macOS version: Sequoia (15)