You should read through the following topic:
Changes in Visual Studio 2017 extensibility
In particular the section that talks about the Visual Studio registry.
As Jose mentioned, I've already posted instructions on using regedit to read/edit this privateregistry.bin at:
Access Visual Studio 2017's private registry hive
The above is also documented in the help topic:
Tools for detecting and managing Visual Studio instances
And an alternative to using regedit, would be to use the new vsregedit.exe utility, which is installed with VS, but I could only find mentioned in the documentation at:
Controlling notifications in the Visual Studio IDE
You can learn more about vsregedit.exe, by running it from your developer command prompt with the /? switch.
Sincerely,
Ed Dore
Microsoft Developer Support