BookmarkCycler от PaulJayD

The "Bookmark Cycler" extension allows you to create a list of "Bookmark Cycler" folders which can then be 'cycled' through with a single click.

That is, each time a listed Bookmark Cycler folder is Clicked, the 'next' bookmark within
that folder is loaded into a new Tab (looping back to the first bookmark, as required).

This allows you to maintain large lists of bookmarks, and ensure that you occasionally
view them all without always loading all of them into tabs.