@terziyski  the tplinkap.net domain has an IP address of 3.224.42.34, which is NOT a local IP address.  That's pretty scary that the AP is silently intercepting the HTTP request and routing it to a completely different IP address, like a man-in-the-middle attack.  But as you say, apparently that is how this AP functions.  Very weird.  Are there other IP addresses that are also silently intercepted and rerouted to some other destination?  If so, what are they?

Through further experimenting and more research I've determined that it is also possible to address the AP directly, using its proper local IP address.  But that requires knowing the local IP address that was assigned to it.  In my case that meant logging into the router that assigned the AP's IP address, and listing its connected devices and IP addresses.