In the Update File form in Community 5.1 there is a 'Comments' field under 'Version Information'. Does anybody know how I can make the field mandatory, so that users cannot upload a new version unless they enter a comment?
You can not do that, at least, not without customizations.
There is an addon that forces users to fill in the metadata, but not in the comments though.
You can find it here GitHub - softwareloop/uploader-plus: An Alfresco uploader that prompts for metadata
An idea would be to understand how it works, and try to addapt it for what you need.
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