Why does adf.error.warn only show on save and close?

Summary:

Using a custom error warning, it only shows on the save and close records, not on the save action.

Content (required):

Using a custom error warning, it only shows on the save and close records, not on the save action. Off course, it needs to be shown on the save action as well. Did someone face this issue as well?

Version (include the version you are using, if applicable):

21D

Code Snippet (add any code snippets that support your topic, if applicable):

adf.error.warn(null)