When I preview my timeline as someone else in my privacy settings, I cannot see f.e. the articles that I currently liked or the comments I wrote. However, when reviewing my timeline, they all appear as publicly visible. Browsing my timeline on a friends iPad showed all the articles that I newly liked.

So my question is:

• Do all likes I put and comments that I write under articles, images, etc. that friends of mine shared, appear for everyone? I did not find any way to remove them from the timeline, except deleting them alltogether.
• Why does the preview of my timeline "as someone else" not display those current likes and comments?