VisualStudio 2022 v17.2.3 has suddenly started changing the namespaces of my C# files when I drag them to a different directory. In the process it also deletes/adds/modifies using statements (often deleteriously) and updates every file referencing the moved file. It's changing the namespace to the ProjectName.FolderPath.
Searching Tools > Options has turned up nothing. I've disabled all extensions in case one of them was responsible, but it's had no effect. How can this behaviour be stopped?