KDevelop currently starts the project parse run when the project has been imported. That's perfect when using single-project sessions, but it means that the import of each subsequent project has to compete with the parser. Project import is a process that can block the UI and should thus take as little time as possible.
This patch introduces a simple queue that holds all newly imported projects until all the imports have been completed; they're handed off to the parser only once the actual import has completed.