Board Thread:Questions and Answers/@comment-26204899-20181103155627/@comment-1684852-20181103172342

There are official policies, look around.

My advise: a) drop a word to the user that added content you do not want stating you do not want any collaboration on your timeline and ask him to leave comments in the your talk page or the articles talk page, or b) report user to Constables.

Unless explicit stated with the appropriate template in the main page of the timeline timelines are non collaborative. The exception are Map Games.