For me more about 2000 than XP. 2000 still felt like a Workstation OS and it was very responsive. XP themeing was the first thing I removed once I could not continue on 2000.
Not to distract from this but if you're primarily using Firefox I really like Container Tabs for this. With the Multi-Account Container Tabs extension, you can set a SOCKS proxy per container, then set certain origins to always open in a given container. You can even use it with Wireproxy to give tabs an individual Wireguard VPN as an exit route, though Firefox can't authenticate a SOCKS proxy so a secure setup may be challenging.
Sidenote: the Firefox VPN integration is lame. For some reason it's only possible to change the destination per container, but seemingly you can't set some containers to be on VPN and some off. I figured the value-add for Firefox VPN (e.g. over just using Mullvad) would literally be deep integration but sadly it's not very impressive. You can do better with Wireproxy.
Senior full stack developer with 7 years of experience, led teams and brought to market products that scaled to hundreds of thousands of users. I'm looking for some extra income and willing to work bellow market depending on the project. I'm open for any suggestion regarding project or finances, just shoot it!