Regex Tester & Validator

This PCRE regex matches lines that optionally start with the German word 'vertretung' (meaning representation/substitute), followed by any characters, then 'payback' (with one or more trailing 'k's), followed by one or more non-word characters (possessive match), and optionally a single lowercase letter. It uses multiline and ungreedy flags, making it useful for scanning German administrative documents or logs for payback-related entries in representation contexts.