In Express.js application the code is sensitive if the https://www.npmjs.com/package/helmet-csp[helmet-csp] or https://www.npmjs.com/package/helmet[helmet] middleware is used without the ``++blockAllMixedContent++`` directive:
In Express.js application a standard way to block mixed-content is to put in place the https://www.npmjs.com/package/helmet-csp[helmet-csp] or https://www.npmjs.com/package/helmet[helmet] middleware with the ``++blockAllMixedContent++`` directive: