In my project, I've got the several include errors:
cannot open source file "freertos/FreeRTOS.h" (dependency of "/home/oisanjaya/.arduino15/packages/esp32/hardware/esp32/3.1.1/cores/esp32/Arduino.h")C/C++(1696)

I think that because of c_cpp_properties.json regenerated each build and missing includePath from ESP-IDF path.

My proposal to fix this issue is adding "${default}", entry into generated includePath inside c_cpp_properties.json so user can control further their includePath using settings from C/C++ extension