I feel a symptom I've been having for a couple of days could be related, but I can't be sure: There's a site I can only access via a personal VPN connection. If

I feel a symptom I've been having for a couple of days could be related, but I can't be sure: There's a site I can only access via a personal VPN connection. If I try to access it while on the VPN, it works immediately. If I try to access it off the VPN, realise it's not accessible because I'm not on the VPN, connect to the VPN and try again, it takes a good 30s to a minute to get to. Feels like Firefox waits some amount of time before making fresh attempts to a previously failed site, possibly due to some caching.