This module allows you to debug the transaction. It can be used to deploy transactions created from Remix and already mined transactions. (debugging works only if the current environment provides the necessary features).
To get to the debugger - you can click the debug button in the terminal when a successful or failed transaction appears there. You can also load the module from the plugin manager and then click the bug in the icon panel. Or you can get to the debugger by running the debug command in the console.
To learn more about how to use this tool go to the debugger tutorial.