To turn the developer tools on, we need to supply the program argument --developer-mode and the VM arguments -ea.
Then they can be accessed in the sidebar panel with the 
icon.
It is also recommended to add --debug to your program arguments to get extra logging output.
To do this in IntelliJ, you'll need to edit your run configuration:
You'll also need to click Add VM options to be given the the VM arguments box, to input -ea.
Specify the settings as follows:
