const regex = /(?:greasyfork|sleazyfork).org\/.*/;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('(?:greasyfork|sleazyfork).org\\\/.*', '')
const str = `https://greasyfork.org/scripts/404275/code
// @include /(?:greasyfork|sleazyfork).org/.*/
// @include /.*greasyfork.org.*/
// @include /greasyfork.org/
// @include /^https://(?:greasyfork|sleazyfork).org/.*/
`;
const subst = ``;
// 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