This is a redo of #63663 which was kind of messed up by rebase.

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I think the name of the feature is misleading. This versioning only keeps the last 10 states which cannot be changed, and versions cannot be deleted or renamed, etc. I think the name auto backup would be a much better fit for this functionality.

I think the name of the feature is misleading. This versioning only keeps the last 10 states which cannot be changed, and versions cannot be deleted or renamed, etc. I think the name auto backup would be a much better fit for this functionality.

This is definitely not a backup! Deleting a project will also delete all previous versions, which is something you would not want from a backup!
Storing more than 10 states and deleting versions is kind of an advanced feature. Anyone wanting this can as well modify the trigger and the qgis_projects_versions table directly. Renaming would be a weird feature, but one could also modify the comments field instead.

Having said that, the 10 states is not a value set in stone, it's just what we thought was a sensible default value so that we do not keep huge amounts of unnecessary projects in the database.

@JanCaha

This pull request has been tagged for the changelog.

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