Try this instead of your rule...
/ip firewall filter
add chain=input dst-port=8291 protocol=tcp

Should work

@ Netlantique : So in Chrome settings, out of the startup options, you have selected the last one, to open a page or group of pages, with only one page set, which is https://www.google.ca? If so, I'd really like to know, where the login tab comes from. If it happened here, I'd try to sniff packets ...

I started to play with this out of curiosity, because it interested me how IE could magically work, while other browsers don't. But all browsers behave exactly the same here, no exceptions. No working IE, no extra tab in Chrome, just plain and simple certificate error in all of them (IE11 in Win8.1...

Can you please confirm that there is no problem with Internet Explorer 11? (I use Windows 8.1) I have tested Internet Explorer over Windows 7 and its not working, still show a Certificate Warning. Firefox also show an certificate warning but Chrome handle this differently, Chrome show a certificate...

You can not buy a certificate to a local IP. All certification's companies require a public IP or public DNS. While what you say is true, there is another way: You can go to http://www.startssl.com and get yourself a FREE level1 SSL certificate for your domain (whoich must exist) and use that DNS n...