How to remove multi-project config

[dr_glenn]

Using ESP-IDF extension in VSCode in Windows 10 Pro.

I wanted my project to have two different targets: ESP32c6 with 2.9 inch ePaper and ESP32s3 with 2.7 inch ePaper. So I used ESP-IDF: Open Project Configuration and then select config with ESP-IDF: Select Project Configuration. I was never able to get this to work for me, despite following examples. I created two project configs: proj1 and proj2 and associated sdkconfig files. The failure was that sdkconfig.proj1 and sdkconfig.proj2 files apparently were never incorporated into sdkconfig, so the config variables were unknown (I confirmed this with #pragma statements in the code).

Now I want to undo the Open Project Configuration and go back to a single target. Multi-config is defined in a file in the project root: esp_idf_project_configuration.json. Since I could not figure out how to revert to a single build target, I simply removed this file. What a disaster! I can no longer build the project because multi-config settings remain in place; for example it is trying to use sdkconfig.proj1 file that I removed and using directory build1 instead of build. I have opened every file in the project, including files in .vscode. None of them contain the settings that were found in esp_idf_project_configuration.json. I've exited VSCode and restarted - still having this trouble.

Where are these settings hidden?