I can create an new mass email and schedule it.
If I change the field 'mailing name' and save it, the changes show in the "Drafts and unscheduled Mailing' - list. But when I click on it the mailing name has reverted back. I confirmed that the changed get saved by looking directly in the mysql DB.
So the saving function seems to work, but latest changes in record does not get loaded in the detailed view.
Reloading the browser does not help. Safari displays a blank page. Reload a second time will display the correct record.
Some users experience a blank page at the second page when registering for an event.
Safari debugger says when showing a blank page: "An error occurred trying to load the resource" with no resources shown.