I do not see the option for "revert to old editor" in the settings menu. I have a XIAO ESP32C6 and need access to the flavours menu. Is this still available and I am missing it?
It is no longer available. In order to ensure a smooth transition to the completely reworked Cloud Editor, Arduino temporarily allowed users to use either the old Cloud Editor or the new one. Once it was determined that the new Cloud Editor had reached a stable state, the old Cloud Editor was permanently removed. So now there is only one Cloud Editor.
It looks like a very nice board!
Although Arduino Cloud has good support for boards based on the ESP32-C3, ESP32-S2, ESP32-S3, and original ESP32 microcontrollers, unfortunately the ESP32-C6 based boards are not currently supported by Arduino Cloud.
Arduino Cloud gains its support for the ESP32 family of microcontrollers from the "esp32" boards platform. Support for the ESP32-C6 was added to that platform only recently in its 3.0.0 release. Arduino has not yet updated the version of the "esp32" platform installed on the Arduino Cloud servers (version 2.0.5 of the platform is currently in use). So the platform installed on Arduino Cloud doesn't support the ESP32-C6.
If you like the XIAO boards, you can use the XIAO ESP32C3 with Arduino Cloud. As for ESP32-based boards in general, you might also be interested in Arduino's own Nano ESP32, which is likewise supported by Arduino Cloud.
As for your XIAO ESP32C6 board, you can use it with the free open source Arduino IDE application. The download links for Arduino IDE are listed here: