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WebStorm enables using numerous run/debug configurations. Each run/debug configuration represents a named set of run/debug startup properties. When you perform run, debug, or test operations with WebStorm, you always start a process based on one of the existing configurations using its parameters.
WebStorm comes with a number of pre-defined default run/debug configuration types for the various running, debugging and testing issues.
Whenever a new run/debug configuration is created, it is based on these default settings applicable to any new configuration of the respective type.