Can not change Additionnal boards preference 2.04

Development Tools IDE 2.x
4

It was actually preferences.txt, and that is only the location for Arduino IDE 1.x.

Arduino IDE 2.x uses a different file to store the configuration:

Windows

C:\Users\<username>\.arduinoIDE\arduino-cli.yaml

(where <username> is your Windows username)

Linux

~/.arduinoIDE/arduino-cli.yaml

macOS

~/.arduinoIDE/arduino-cli.yaml

The configuration options are documented here:

https://arduino.github.io/arduino-cli/latest/configuration/#configuration-keys

  • board_manager
    • additional_urls - the URLs to any additional Boards Manager package index files needed for your boards platforms.