Create a custom guide, give it a name, but don’t close the template editor; it still shows up as “Untitled Guide” in Guides menu and any dropdowns where guides of that type would show up (e.g., BWS Guides in the right-click menu). Only after you close the template editor does the rename take effect in other places where that guide's name occurs.
This is different from what seems to be the new philosophy of L4 which is that you don't need to close things in order to save them. With Collections, for example, when you give a new "Untitled Collection" a new name, it gets changed immediately, so that when you drop down the "Open" menu in the Collections tile, the new name shows up and not "Untitled Collection." I don't particularly like the fact that there's no sense of when something gets "saved" anymore, no need to save it intentionally. But that's not what this bug report is about. If you're going to go with that model, be consistent about it. Have it work that way with Guides. too.
