By the way, is there a safer way to get the xpriv root bip32 to import into bitcoin core as a descriptor without using iancolam.io, since it is an html file that opens in the browser?
I don't use Bitcoin Core so I don't know the answer to your question. However, you should download the IanColeman tool and use it offline on an airgapped setup. That's the safest and most recommended way to work with it. If you use the tool on an airgapped computer, nothing can leak from it, which isn't the case when you use it on an internet-connected PC.