Can I have more than two levels of categories/folders?

Two levels of folders is generally the most efficient for quick and reliable retrieval. (I keep over 4,000 bookmarks in my main list.) However there are already a number of ways of extending this:

• Create multiple subcategories, e.g:
  Shopping :: Shops (books)
  Shopping :: Shops (music)
  Shopping :: Shops (gifts)
• Use separators with text to visually subdivide items
• Split your bookmark collection into two or more lists, e.g. work and leisure, or shared and personal. This effectively gives you an extra level.

I am working on how to support more levels without over-complicating the user interface.

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