Using older versions of Outlook for Mac for personal email and calendar
Same problem here. pinwheel of death for about a minute, then comes good and I'm able to continue with composing the message.
Seems to happen more frequently when converting the typed-out smiley face i.e. :-) as opposed to inserting an emoji from the touch bar.
Outlook mac version has been very buggy with other reply window issues as well. Sometimes upon typing first character in the body freezes the entire app indefinitely, requiring a kill/force quit.. Once the app is reloaded, trying to resume composing the message cyclically encounters the same problem. I've had to log on to the OWA to discard the problem draft email to restore stability in the app.
Running outlook for Mac (via the mac app store) version 16.67 (2211300)
This issue has not resolved itself over several app updates.
Please help!