The Private Bookmarks extension allows you to use a special folder password protected bookmarks. You can put personal bookmarks in it, which can only be viewed after entering the password.
After creating a secret folder, in the section "Other bookmarks" a new folder appears "Private bookmarks". You can add and remove your links from it and lock them when you're done.
Whenever an item is added/removed, the contents of the folder are encrypted and stored on your car. When closed, the folder itself is removed from your browser's bookmark collection. You can move/rename the folder and the next time you unlock it, it will appear in that location and with that name.
Shortcuts to manage the extension:
Option+Shift+8 opens the private folders menu in a new tab.
Cmd+Shift+8 adds the current page to your private bookmarks.
Cmd+Shift+F8 adds all tabs opened in the current window to your private bookmarks.
Ctrl+Shift+L / Cmd+Shift+L locks the private folder.