const regex = new RegExp('(\\n)[\\r\\n]+|(<text>.*?</text>)', 'isug')
const str = `String 1
String 2
<tag1>
Tag str 1
Tag str 2
</tag2>
<text>
Text
Text 2
Text 3
</text>
`;
const subst = `$1$2`;
// The substituted value will be contained in the result variable
const result = str.replace(regex, subst);
console.log('Substitution result: ', result);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions