Unsolved Qt Creator cmake problem

[jronald]

1. Environment
   Qt Creator 4.12.4 for Linux
   cmake 3.18.1

2. Reproduce the problem
   2.1. create a cmake project named ProjectA, i.e. project(ProjectA LANGUAGES CXX)
   2.2 From menu, Build / Run CMake, on the bottom of the left sidebar, with the first button, there the build type (debug / release / ...) and project can be choosed, in the case ProjectA
   2.3 change the proejct name to ProjectB in CMakeLists.txt, do step 2.2, ProjectA and ProejctB are both there, found no way to clear the old name except deleting CMakeLists.txt.user. (EDIT: please create more than one projects, so the names will be displayed explicitly.)

3. Question: any way to clear the old name easily? In other words, Qt Creator only add new projects to CMakeLists.txt.user, never delete old & nonexistent projects from CMakeLists.txt.user, right?