The Replace Variables action replaces variable reference (ie %VariableName%) in a block of text with their current variable values.
Text can be loaded from a file or from another variable, and can be saved to either a file or a variable.
Source text can be loaded from a variable or from a file on disk.
If this option is set and a variable name is referenced but not defined, the action will fail. Otherwise, the variable reference will be deleted (ie replaced with an empty string.)
Enable this option in order to echo the replaced text to the action's log output.
If selected, the source text (file or variable) will be overwritten with the new text. If this option is not selected then you can choose a file or variable to write with the new text.