Regex Tester & Validator

This regex matches words or phrases starting at a word boundary, using a lookahead to require at least four word characters followed by a non-digit. It captures either the literal phrase 'beautifül tree' or sequences of word characters including German umlauts (äöüÄÖÜß), with a lazy match to keep results minimal. With global and case-insensitive flags, it is useful for tokenizing German text or extracting words containing special characters from multilingual content.