We have submitted our outlook plugin for certification and received the following message back:
"The add-in did not pass compatibility tests for Outlook on the Web in Safari (Version:13.1(15609.1.20.111.8)).
Nothing appears to be launched when we click "Schedule" button in message read mode in the above browser."
We can reproduce this locally, but the cause is that the pop-up blocker is blocking the window that office sdk is attempting to open when we call Office.context.mailbox.displayNewAppointmentForm. Our plugin does not specifically call window.open.
We have also tested this behavior in Firefox and we get the same results. Please let me know how to go forward from here.