I found out that the problem was that I was using port 8080 which was blocked by my ISP. I managed to get it to work using a different port (port 8443 didn't work either).
Now I need to ask this: if I want to put my app behind Apache's reverse proxy, do I need to set up port forwarding for just the port that I set for the reverse proxy in ProxyPass directive, or do I also have to do it for the one Apache is listening on?
Also, I got a free DynDNS from dynu.com and I'm serving my app on port 5501 on it, but is there no way I can use a URL where specifying the port number isn't a requirement? The URL is http://dragonosman.dynu.net:5501/ . And if I want to get an SSL certificate for it, seeing as I'm hosting it on my own computer with a Dynamic DNS, how do I prove ownership of the domain when I try to use something like this? https://www.sslforfree.com/ .
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