Bookmark disappeared from Tools menu!

Hello,

 

Strangely, Bookmarks disppeared from the Tools menu. It's not that I installed a plugin and then it dsiappeared, it was there and then it wasn't there. Furthermore, bookmarks are working just fine when I use "Bookmark this" from sidebar.

 

Like nothing wrong is with the bookmarks itself, it's just the Bookmark item that hae escaped from the Tools barn and I wonder if anyone can help me bring it back?

 

Thanks very much!