Perhaps the Redirect app could serve this purpose?
References:
https://doc.yunohost.org/oc/admin/apps/custom_apps/#adding-a-custom-tile-in-the-portal-pointing-to-an-external-app
App itself:
Otherwise…
you can also add in a description at the top of the portal by entering your root Domain record in the administration panel
Using Custom user intro in the default tab - Features, you can enter HTML, just as I have.
It will then be visible just under the username after logging in.
