Can't Connect to TCAdmin via Browser

[Bull]

I've been a Windows user since Windows for Workstations 3.1 and decided to host a Rust server.  My 'tech support' friend is big into Linux and suggested I run it under Linux instead of of Windows, so I built a Linux PC (Debian 12 CLI-only version - as advised) and he guided me through the Rust server setup.  It runs great.  Players are happy.  I have been using RCON, LGSM and Putty to run it for several months.  Now I'd like to switch to TCAdmin and have installed it on the Debian box.  I want to administer the server from my Windows 11 PC on the same network.  I've created Windows firewall rules for my browser (Brave) allowing access to ports 8880, 8881, 8890 and 8891 for both TCP and UDP traffic.  I opened these same ports in my router under Transmission > NAT > Virtual Servers (uPnP is disabled for security).  At this point I attempt to connect to my Rust server using http://public_ip:port (substituting port for each of the four above) as well as http://local_ip:port (again, substituting port for each of the four above) but cannot connect.  Brave returns this:

Any help would be very much appreciated.  Thank you.

Edited April 20 by Bull
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