Change default file format for multiple users

Hello,

We are trying to override the default configuration on 100+ Ubuntu 16/18.04 systems for LO 6.3 from ODF to OOXML.

We can edit the xcd files and that works, however this is not persistent. A separate file in /usr/lib/libreoffice/share/registry with the configuration works, sometimes. I have it working completely and have had it fail to work on other systems.

I tried creating a extension using the guide below but failed so far. Debugging is very hard and the syntax quite complex.

https://wiki.documentfoundation.org/images/b/b0/LibreOffice_config_extension_writing.pdf

Has any one found a definitive way to override the default configuration to OOXML for LO?

Many thanks for any help on this in advance.

What do you mean by changing from ODF to OOXML? LibreOffice uses the defined international standards .odt, .ods etc. Ms Office uses a variety of versions of .doc, .docx, .xls etc. They are not interchangeable. My writer documents cannot be saved as a .doc or .docx.

Is there a good reason why you are attempting to make this change to the normal defaults, and how can you limit the LibO functions when creating documents?

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I think it clearer to use the actual file types you are considering. Open Document Format (ODF) is the family of International Document Formats. So for text documents you need to talk in terms of Open Document Text (.ODT), spreadsheets .ODS. These are NOT LibO formats nor unique to LibO.
Similarly when you talk about OOXML formats you are actually talking about a VERSION of .docx, .xlsx used by OnlyOffice. OnlyOffice does not support .ODT or .ODS directly, it reads or writes them on INPUT and EXPORT.

On my Linux Mint LibO English-UK system it is possible to Default to a version of .docx etc. by setting the options in TOOLS > OPTIONS > LOOAD SAVE > MICROSOFT OFFICE > EMBEDDED OBJECTS.

You thus have two conversions between LibO and OnlyOffice. Both are not recommended.

As I said earlier, I would expect you to have problems, and certainly my documents would not be able to transfer completely.

I know this is not the advice you were after.

It is required for better compatibility with OnlyOffice which we use in Nextcloud. We were using Collabora but it had serious performance issues. We would prefer ODF but it is not working out so using OOXML should keep us away from switching to MS or Google.

We have not seen any issues saving to OOXML so far, we have a number of users doing this already.