- CTRL+D: Add a bookmark.
- BACKSPACE: Move back.
- CTRL+B: Open Bookmarks in browser sidebar.
- CTRL+I: Open Bookmarks in browser sidebar.
- F7: Toggles Caret Browsing on/off.
- CTRL+W: Close current tab.
- CTRL+F4: Close current tab.
- ALT+F4: Close current window.
- CTRL+C: Copy.
- CTRL+X: Cut.
- CTRL+MINUS: Decrease text size within web page.
- SHIFT+DEL: Delete an individual form.
- CTRL+J: Launch Download Manager.
- CTRL+G: Find again.
- SHIFT+F3: Find previous.
- F11: Put the current browser window in full screen mode.
- F1: Launch Firefox Help.
- CTRL+H: Display your browsing history.
- ALT+HOME: Load your home page.
- CTRL+PLUS: Increase text size within web page.
- F6: Move to next frame.
- SHIFT+F6: Move to previous frame.
- CTRL+T: Create a new tab.
- CTRL+TAB: Make the next tab active.
- CTRL+N: Open a new browser window.
- CTRL+O: Launch the Open File dialog.
- CTRL+ENTER: Open a link in a new tab.
- CTRL+U: Display the source of the current page.
- CTRL+V: Paste.
- CTRL+PAGE UP: Make the previous tab active.
- CTRL+P: Print.
- F5: Refresh the current page.
- CTRL+F5: Refresh the current page, overriding your cache.
- CTRL+S: Open Save Page As... dialog.
- ALT+ENTER: Open Save Link Target As... dialog.
- CTRL+A: Select all.
- CTRL+L: Select location bar.
- CTRL+DOWN ARROW: Select next respective search engine in search bar.
- CTRL+UP ARROW: Select previous respective search engine in search bar.
- CTRL+Z: Undo.
Thanks to Scott Orgera, About.com Guide