example.com works as well. it doesnt redirect to https://example.com
There's actually a huge list of domains that macOS/iOS try: http://stackoverflow.com/questions/18891706/ios7-and-captive...
I have never seen a captive portal interceptor on MacOS (much to my disappointment), only iOS. Is there some setting I previously screwed up?
Here's a screen shot I found: https://www.wireless.bris.ac.uk/gfx/eduroam-osx/captive_port...
Because of this thread I simulated it on my network and couldn't cause it to show up.
I'm sure there are plenty of others, but someone might remember that URL over another so I thought it would be helpful.