How do I import my Safari bookmarks into Firefox on a Mac?

I’ve tried Googling, but Firefox’s instructions don’t work.

Going to “bookmarks,” then “show all bookmarks,” then clicking “import bookmarks from HTML,” and clicking the HTML file, but it doesn’t work. The bookmarks don’t show up anywhere in the “Library” window.

Dragging and dropping doesn’t work.

I don’t want to import any other settings from Safari, just bookmarks.

I’m using Mac OS 10.7, Firefox 19, and Safari 6. (I just upgraded to the latest version of Firefox today.)