Yes it runs on Linux, my laptop is running Manjaro and I installed it from the AUR. I’m not sure if the scripting is possible, there is an openAI compliant web API you can turn on so maybe possible through that, you would probably have to feed in the content of the site with the prompt though, I’m not sure there is a better way but I guess that sort of behaviour is a bit out of scope for GPT4All.
There is a local documents feature that allows it to access text files on your machine that you give it specific access to but I think it’s fairly limited in its ability.
+1 for namecheap. I’m happy with them as a registrar. Their support has always been fast and helpful if I have an issue. I use CloudFlare for DNS as they were easier to setup something for dynamic IP.