如何把 bookmarks.html 转换成树状结构/下拉菜单的网页？

Firefox 输出的 bookmarks.html 是一页平铺的网页，网址多了就会很长， 如何把 bookmarks.html 转换成树状结构/下拉菜单的网页？ 点击后才下拉子菜单的地址，（或另页打开） 最好是能自动转换

How can I convert the Firefox bookmarks.html into a drop-down/tree-view web page? Right now, the exported bookmarks.html is a one page html, which can be a very long list,  How can I convert it into a drop-down/tree-view html page (or pages) automatically? so I can drop-down the sub-tree only when I needed to.