Firefox ignores hosts file when tethered to iPhone
When connected to regular Wifi, Firefox respects the /etc/hosts file. However, when tethered to an iPhone, Firefox does not respect the /etc/hosts file. (Neither does Chrome, for what it's worth). Other programs such as Postman, and traceroute, still respect the hosts file, it's just browsers (including Firefox) that do not.
The behaviour is perfectly repeatable - by switching from wifi to tether and back again, the problem goes away/comes back.
My use case is blocking domains like googletagmanager.com . When on Wifi, firefox does not load anything from that domain. However, when tethered, Firefox does load content from that domain (even though Postman still cannot).
I am using Firefox 72.0.1 and Macos 10.14.6
Is this a setting? A bug? It is certainly not expected behaviour.