Broken invitation email for 18.04

We recently upgraded a self hosted Nextcloud to 18.04 and while everything work fine, the invitation email messages sent upon creating a calendar appointment are completely messed up.

This only happens if the appointment is generated inside Nextcloud; when creating an appointment from a Caldav-connected Thunderbird / iOS calendar the message is fine. Anyone experienced the same?

What do you mean? How are they broken?

Thanks! I’m including an image with the rendering on Thundebird, same in iPhone anyway. Willing to share the message source if useful.

calendar

Thanks! Could you please open an issue on https://github.com/nextcloud/server with all required information and the message source (with personal information filtered)?