Vaadin loses server connection


my Problem is, since i changed the spring boot server configuration of tomcat to https,
vaadin is loosing the server connection ( shows it ) on the Login dialog…

The page gets displayed but immediately loses connection, displaying the “trying to reconnect” message ad perpetuum.

(I use Vaadin 14 Flow)

I figured out:

if i do this

in method
void configure(WebSecurity web)

then it works…
This means in my eyes, this :

// Vaadin Flow static resources

				// the standard favicon URI

				// the robots exclusion standard

				// web application manifest
				"/manifest.webmanifest", "/sw.js", "/offline-page.html",

				// icons and images
				"/icons/**", "/images/**",

				// (development mode) static resources

				// (development mode) webjars

				// (development mode) H2 debugging console

				// (production mode) static resources
				"/frontend-es5/**", "/frontend-es6/**");

filters something what is needet …