I have a connection to a local host on another computer (it's actually dump1090 which is feeding software for ADSB signals from aircraft). The host computer dual boots and the software runs on Windows 7 and Linux Mint and should produce a page with a map plus other details on port 8080. My "viewing" computer is Firefox ESR on a Macbook. When the host is running under Windows all works fine. But when it's running in Linux my Macbook won't open the page. I get "Connection is not secure" when I click the circled "i" and when I go to "More information" there is no permissions tab - just General, Media and Security. Under General it says "Web site: 192.168.0.100:8080", "Owner: This web site does not supply ownership information.", and "Verified by": Not specified". Well the website is being generated on the other side of my table, I own it, and I will vouch for it! So how can I tell Firefox that when there's no permissions tab??? And why should it work fine when the page is being created in Windows and not when it's being created in Linux? I don't need that answered really - I just want a way of overriding Firefox's "Connection not secure"!!