The same release note, the same POST .../changes with no importance, on a 17.10 wiki: only the change template differs.
Before, the change is stored as ReleaseNotes.Data.MyProduct.3.0.Entry001.WebHome and the note says "No changes!":
After, the template gives it importance = 1 (Medium) and the note displays it:
Fixed by giving ChangeTemplate an importance of Medium, as decided. Creation is template-driven for every caller, so the wiki UI, the Java API, the script service and the REST endpoints are all fixed by that one value. Regression-tested in ReleaseNotesIT#contributorsListAndChangeNumbering, which now saves its change without touching Importance and asserts the release note displays it.
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