Fixed: Microsoft Edge can't see or open VirtualBox-hosted local web sites

I'm using VirtualBox on a Windows 10 machine along with Docker to deploy ASP.NET websites to local Linux Containers. To be clear, this isn't accessing websites with http://localhost, this is accessing locally an VirtualBox virtual network.

For example, my local IP and subnet is here, but my VirtualBox is here:

Ethernet adapter Ethernet:
   IPv4 Address. . . . . . . . . . . : 192.168.0.140

Ethernet adapter VirtualBox Host-Only Network:
   IPv4 Address. . . . . . . . . . . : 192.168.99.1

Make sense? A Linux VM running Docker containers is then http://192.168.99.100, for example, on various ports.

Strangely, however, I was unable to access these VirtualBox-hosted websites with Microsoft Edge, while they worked on Chrome and Firefox. I wanted to fix this. Just saying "use another browser" isn't enough, I like to figure it out.

I ended up trying this, and oddly, I was right. Go to Start, type "Internet Options" then then the Security Tab, then click Local Intranet, then Sites. Add your Virtual Machine's IP (in this case, the Docker Host) in that list and you're golden.

Now about the WHY....I have no idea. I'll report back as I keep poking around.

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