You can revert a bookmark that you have published to being unavailable to others by unpublishing it.
Do the following:
From the app overview, click to view the bookmarks.
- Find the published bookmark under Published by me.
Long-touch/right-click the bookmark and select Unpublish.
The Unpublish bookmark dialog appears.
The bookmark is unpublished and moved from Published by me to My bookmarks.
The bookmark is no longer available to other users of the app.