I've got a new beta release out on Github for V4.0 of this project, The principal change is that I have removed all the face recognition code/UI, resulting in a much smaller codebase that allows for Over The Air updating (OTA). Super handy if you want to mount the camera in an inaccessible location.

* The programming instructions have changed - The boards manager entry for the AI-Thinker board does not use OTA compatible partitioning, so you need to choose a Generai ESP32 dev board entry, select the correct partitioning, and enable PSRAM in the GUI. See the updated README

* There are some other fixes for Video quality issues that should be useful

* The OTA update can be secured with a password to stop the unit being hijacked

* There is a fix to allow using the ESP Arduino IDE Core v2.x (currently in beta) and I have been testing with this for a few weeks now, no issues seen. If anything the performance and video quality are better.