To find BADI, the first step is to go to the SE24 transaction and display CL_EXITHANDLER class. Then double click on the GEL_INSTANCE method and put a breakpoint on the class method CL_EXITHANDLER=>GET_CLASS_NAME_BY_INTERFACE.
Run the transaction you need to find BADI in a new screen and it will automatically stop at the breakpoint you put in SE24. Each time you execute in debugger it will display the BADI names.
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