As you have the same problems using Chrome and firefox…
Sorry but i seldom use vpn myself, can’t give you a remote training to set this up.
I think you’ll have to turn off the firewall or make an exception for the victron site.
But, as someone has written here before, the 10+ year old Mac doesn’t fit in the modern world. Every 300$ windows pc is more reliable.
Apologies assumed you had the default config from your post link.
So the spec is ok.
Can you switch off https on the gx in the vrm menu. Might be part of the issue was one suggestion.
The main thing really mac itself is not updating the machine OS or developing it anymore. Citing that their framework can’t do it.
Not sure how everyone else is supposed to do that for them. If anything they made their money out of you and now the system is software obsolete. Those specs otherwise are more decent than my current laptop lol.
It’s controlled by a registry setting, my computers don’t do that. The siemens software that i work on is certified and tested on one build of windows 10, my pc’s keep this in place.
Like 90% of all software, it will not run on Apple