Hi @joergmschulz ,
We understand the inconvenience caused by the current inability to open template files (OTT, OTS, OTP, OTG) in Collabora Online / Nextcloud Office.
Please note that there is an ongoing discussion regarding this issue, and potential solutions are being considered for future updates. You can follow the progress and participate in the discussion here: GitHub Issue #2315.
We appreciate your feedback as we work towards a resolution.
Thanks,
Darshan