I searched this community and couldn’t find anything about odt, I found a few odt viewers on F-Droid and Aurora when I searched ‘odt’, but the only editors for odt, were ironically the proprietary Google Documents and Microsoft Word.
Have you found anything else?
I haven’t used it but looks like Collabora does it. You can add their report to f-droid: https://www.collaboraoffice.com/releases-en/collabora-office-on-mobiles-supporting-password-protected-documents-and-available-on-f-droid/
Unfortunately, it’s not available in the official F-Droid repository, but only by Collabora’s own F-Droid repository. I don’t want to trust other package managers except those of the official F-Droid repo.
But it’s the official Collabora repo?
May I ask why? Using alternative sources from the vendors themselves usually isn’t any less secure than using the official F-Droid repos. It’s a common thing on Linux.