Unable to load https://email.ionos.com/

[KirilOkun]

Tried to add another email account hosted by Ionos but after specifying the url for a new tab and enabling the sandbox setting the login window opened in a regular browser window but never loaded in ElectronIM. Logging in opened the email interface in the browser and not in ElectronIM, where the page continued to show "Loading...".

Disabling the sandbox setting loaded Ionos webmail login screen in the ElectronIM but after logging in the email client opened in a browser window while IM continued to show the login screen.