assertTrue("Content should end with }", contentNew.trim().endsWith("}"));
        assertTrue("Content should be substantial", contentNew.length() > 100);

        // Verify it contains expected mapping fields
        assertTrue("Should contain properties definition", contentNew.contains("properties"));
    }

    /**

During crawling and indexing, Fess:

1. Detects language from document content using Apache Tika
2. Validates against `supported.languages` list
3. Creates language-specific fields (e.g., `content_ja`, `title_en`, `content_sv`)
4. Applies language-specific analyzers for better search results

Configured in `fess_config.properties`:
```properties
indexer.language.fields=content,important_content,title
```