const regex = /((?=<[^>]>)[^;]+;[^;]+;|<[^>]>|<\/[^>]+>|<[^'"]+['"]|['"][^<]+<[^>]+>)/gm;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('((?=<[^>]>)[^;]+;[^;]+;|<[^>]>|<\\\/[^>]+>|<[^\'"]+[\'"]|[\'"][^<]+<[^>]+>)', 'gm')
const str = `Customers are advised to follow <A HREF='https://support.microsoft.com/en-ph/help/4343902/security-update-for-adobe-flash-player' TARGET='_blank'>KB4343902</A> for instructions pertaining to the remediation of these vulnerabilities.<P> <P>Patch:<br/> Following are links for downloading patches to fix the vulnerabilities: <P> <A HREF='https://portal.msrc.microsoft.com/en-us/security-guidance/advisory/ADV180020' TARGET='_blank'>ADV180020</A>`;
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