The STR haven't been reproduced by me, and they're intermittent. But here they are as best I understand (1) Open Firefox and run it without any VPN connection. (2) Enable VPN to school. (Cisco AnyConnect if it makes a difference.) (3) Try to load an article from uptodate.com. Intermittently fails. (4) Try to load the same article in Safari. Succeeds. I don't know if the articles load properly in FF if it's exited and then restarted after enabling the VM. It seems that some state related to enabling the VM isn't updated in gecko.