Clientless RDP user credentialsFollow
The first time a Clientless RDP app is opened, the user will be prompt to fill in their credentials. You can also create credential sets from the "Integration credentials" settings page.
The credentials are the credentials for the VM and/or Remote App. This can be a username (without domain) or UPN. You can choose to which apps you like to link different integration credentials.
To change the current credentials go to the options menu and "Settings". Click "Integration Credentials". Fill in the new credentials, link it to a ClientlessRDP app and click "Done"