How to set-up ABAP language in Notepad++ : https://blogs.sap.com/2017/02/20/abap-syntax-highlighter-and-code-folding-in-notepad/.
Retrieve UDL file here : https://blogs.sap.com/2014/02/12/abap-syntax-highlighting-in-notepad-part-2/ (copy XML code into a text file and save it as XML file).
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