The ability to share a dashboard with someone in a different O365 tenet is no longer working. It has been working for months and now throws an error message "Failed to send email to invite users . . ."
Looking around, this appears to be a known issue that was supposed to have an update yesterday 1/18. I lost that message and link and couldn't find it again. There was no apparent update on 1/18.
I do publish with the January 2018 desktop Power BI application under a PRO license. I need to add the next wave of users.