In Outlook for Mac, an office.js Outlook add-in runs in a task pane that I assume is a Safari web control. I have not been able to determine how you clear the cached files from an add-in running in the task pane.
Does anyone know how to manually clear the task pane's browser cache? I cannot find an official answer, just guesses.
Thanks.
Seems like the documentation contains the information you're looking for: Clear the Office cache
For Mac:
Delete the contents of the folder:
~/Library/Containers/com.Microsoft.OsfWebHost/Data/