How to edit or delete a timeline post

Summary

Past posts show edit and delete controls. Each post can show Posted by. At least one post must remain.

Who can do this: Owner, Admin, or Editor.

An incident with timeline history.

Open the incident detail page.
In History, find the post.
To edit: click Edit timeline post, change fields, then click Save post.
To delete: click the delete control, confirm Delete this timeline post?, then confirm delete. You cannot undo this.

[Screenshot: Timeline History with Edit timeline post and delete confirmation]

The timeline reflects the edit, or the post is removed. Public pages update accordingly.

If delete is blocked, you may be trying to remove the only remaining post (At least one post must remain.).