Similar to clipboard.write() clipboard.read() throws a 500 error when used inside a Personal tab app - but only within the Microsoft Teams app. In the browser, this does work.
{"errorCode":500,"message":"An internal error occurred"}
Unfortunately unlike the copy event, pasting through the html apis is not possible in either the browser or desktop app:
NotAllowedError: Failed to execute 'readText' on 'Clipboard': The Clipboard API has been blocked because of a permissions policy applied to the current document. See https://crbug.com/414348233 for more details.