Hello, CMake Team.
From the research of this topic, it appears that the issue is actually a bug from Sphinx itself. Therefore, it can be resolved by fixing the issue in a new version of Sphinx. However, some old versions of CMake files can only be built using old versions of Sphinx, so they won’t be able to fix this issue. This is why I hope the CMake team will continue to maintain the Sphinx documentation system for older versions of CMake.
Additionally, I hope that the CMake project, like other projects using Sphinx, would prepare a requirements.txt file specifying the required Sphinx version and other dependencies. This way, users only need to run pip install -r requirements.txt before building the documentation, without worrying about which version of Sphinx to install. For instance, to build documentation for all versions of CMake, I had to prepare corresponding requirements.txt files in the project as shown below:
If CMake project can prepare a requirements.txt, then this code can be removed. All I need to do is to find the requirements.txt and run pip install -r to install it.