Please add Previous/Next bookmark arrows in the header for bookmarks. This would enable quick switching between bookmarks and would be especially useful when bookmarks have been created with such motion in mind, eg a set of bookmarks for each year - could rapidly move next/next/next through them without having to pull down the bookmark menu…
Yes, there comes a time when too many bookmarks becomes a management issue. Eventually, there will need to be more management options for bookmarks, although, I guess some users are hitting that situation sooner than others. 
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