Test, validate and match regular expressions
Matches simple HTML/XML opening and closing tags containing only lowercase letters, such as `<div>`, `<p>`, or `</span>`. The optional escaped forward slash captures closing tags, while `[a-z]*` also permits empty tags like `<>`. With global and multiline flags, it finds all occurrences across every line. It won't match tags containing uppercase letters, digits, hyphens, underscores, or attributes.