Service Hub DNS Domains for Proxy Whitelisting:

Production

App / Functionality	URL
Portal	https://portal.secure-service-hub.com
Gateway (ServiceHub API)	https://gateway-prod.secure-service-hub.com
Excalidraw (Conferencing: Whiteboard)	https://firestore.googleapis.com
	https://firebasestorage.googleapis.com
	https://excalidraw.secure-service-hub.de
	https://excalidraw-room.secure-service-hub.de
Jitsi (Conferencing: Video)	https://jitsi-prod.secure-service-hub.de
Matrix (Conferencing: Chat)	https://matrix-prod.secure-service-hub.io

App / Functionality	URL
Portal	https://portal-staging.secure-service-hub.de
Gateway (ServiceHub API)	https://gateway-staging.secure-service-hub.de
Excalidraw (Conferencing: Whiteboard)	https://firestore.googleapis.com
	https://firebasestorage.googleapis.com
	https://excalidraw-staging.secure-service-hub.de
	https://excalidraw-room-staging.secure-service-hub.de
Jitsi (Conferencing: Video)	https://jitsi-staging.secure-service-hub.de
Matrix (Conferencing: Chat)	https://matrix-staging.secure-service-hub.de

App / Functionality	URL
Portal	https://portal-test.secure-service-hub.de
Gateway (ServiceHub API)	https://gateway-test.secure-service-hub.de
Excalidraw (Conferencing: Whiteboard)	https://firestore.googleapis.com
	https://firebasestorage.googleapis.com
	https://excalidraw-test.secure-service-hub.de
	https://excalidraw-room-test.secure-service-hub.de
Jitsi (Conferencing: Video)	https://jitsi-test.secure-service-hub.de
Matrix (Conferencing: Chat)	https://matrix-test.secure-service-hub.de

App / Functionality	URL
Portal	https://portal-development.secure-service-hub.de
Gateway (ServiceHub API)	https://gateway-development.secure-service-hub.de
Excalidraw (Conferencing: Whiteboard)	https://firestore.googleapis.com
	https://firebasestorage.googleapis.com
	https://excalidraw-development.secure-service-hub.de
	https://excalidraw-room-development.secure-service-hub.de
Jitsi (Conferencing: Video)	https://jitsi-dev.secure-service-hub.de
Jitsi (Conferencing: Video)	https://jitsi-development.secure-service-hub.de
Matrix (Conferencing: Chat)	https://matrix-dev.secure-service-hub.de
Matrix (Conferencing: Chat)	https://matrix-development.secure-service-hub.de

If your firewall is not configured correctly for SSH and the corresponding ports are not released, difficulties may occur.

One example is that graphics shared with the other person on the whiteboard are not displayed correctly:

The URL that has to be whitelisted for displaying images on the whiteboard correctly is: