Dirty old town?

Although not an acronym, I prefer to reference this as a 'meatware' issue

I prefer Wiztree to WinDirStat. It uses the NTFS journal somehow to make it incredibly fast to scan your whole drive

What makes you think that? Their website has instructions for installation via a Linux box. https://www.ventoy.net/en/doc_start.html

Adding on to other suggestions, if you're not aware of Ventoy it's a very handy tool. Using it you can have a USB drive with several live images on it which you can choose at boot time. Great for quick testing, just drop an ISO in a folder!

It's called CIDR notation, the number represents how many bits of the whole address represent the "network" part of the address. /8 is equivalent to a subnet mask of 255.0.0.0