After wasting a lot of time installing older plugin versions, thinking they were causing the issue, I eventually realized that the real problem was the folder path. What I called C:\xampp\htdocs\projects\project was actually C:\xampp\htdocs\projects\project 1.0, and probably the space between project and 1 (also the point between 1 and 0 is not something I will ever put again) was the root cause of everything. I’m not entirely sure whether the error was caused by the URL ending with project%201.0 or by something closely related. What I do know is that after renaming the folder to just project, everything started working correctly.
