I have spent some time overcoming numerous obstacles to making Collabora and Nextcloud work together. I thought it might be useful to share some of the obstacles for me along the way.
1: Install nextcloud on its own subdomain. The documentation tells you this, but it can be a pain if you have to move your Nextcloud. The Nextcloud install should be at: https://yournextcloud.yourdomain.ext not at https://yourdomain.ext/yournextcloud. The latter will not work.
2: Use the correct Nextcloud plugin. The current names are not intuitive in Nextcloud. As of now (July 2024), Nextcloud offers two apps called “Collabora Online - Built-in CODE Server”. These are not the correct ones. The one called “Nextcloud Office” is correct. When viewed, the URL points to “richdocuments.” This is all confusing.
3: Configure the server location correctly: “Use your own server” and put the URL of your Collabora server in the box. Note: you must allow access to “visitors” in the application permissions in Yunohost. This seems counterintuitive from an access control standpoint, but it simply does not work otherwise.
4: Configure the WOPI request allow list correctly. The highly frustrating and super secret key to making this work with a default Yunohost install is to include both the IPV4 and IPV6 loopback addresses, even if you otherwise don’t use IPV6 (eg. your ISP doesn’t offer it, or whatever). If you run in Docker, you’ll need to google up a better answer (it’s out there, but not completely intuitive).
I hope that’s helpful to others trying to get this working.
Lastly, after some testing, I have tentatively concluded that despite the presence of Collabora documentation indicating Mail Merge is available, it does not actually appear to be functional when installed with Nextcloud by Yunohost in the default ways. The tabs / dialogs for data sources which work in LibreOffice locally, are not present in Collabora, even when viewing documents which already have mail merge fields pointing to external data sources. Otherwise, it appears to work nicely for the basics.
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