When an artifact is set with a higher priority than another:

• For the "subject of action" (ie. the artifact being dragged and dropped), there is a new entry in the follow-up comment that highlight this change
• For other artifacts (environement), from where it was dragged and where it's dropped, there is no information about this change
• The change message displays that the priority was increase or lowered
• When there are multiple move, each "subject of action" is referenced

Hence, for artifact "subject of action", in the follow-up section of the artifact, we will have a message like:

• On Sept 4th, Manuel increased priority of artifact, it was placed before/after "story #85"

When using Planning v2, we have more context information about this priority change. We can detect in which milestone the change was made (Top backlog, Product, Release, Sprint...). In this situation, the follow-up will be like:

• On Sept 4th, Manuel increased priority of artifact in sprint #12, it was placed before/after "story #85"

The recording of the priority changes is an opt-in at tracker level (the tracker admin has to enable the logging of priority changes).

This story doesn't covers the inclusion of this information in REST route /artifacts/:id/changesets