Hello Marco De Toni,
Thank you for reaching out to Microsoft Support!
It looks like you're on the right track with using the Microsoft Graph API to extract Loop files in HTML format. However, as of now, the version API for extracting Loop files in HTML format is not supported.
The current API allows you to retrieve the contents of an item in a specific format, including HTML, but this functionality does not extend to specific versions of the item. You can only get the metadata of Loop files and not the contents directly, as they are encrypted.
You can submit this feature request using this support link, which will be monitored by Microsoft team and make the enhancements to Graph API.
Hope this helps.
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