I have a reference to an item that uses the sitecore:
protocol:
"sitecore://master/{...GUID HERE...}?lang=en&ver=0"
I could attempt to parse this URI manually to look up the item, but I'm pretty certain there's an existing utility somewhere to do this.
Of course, searching for sitecore:
protocol URIs leads to a lot of answers about generating URLs from items, and that's not what I want in this case.