Press the Menu button on firefox the 3 layer one button, then inside go to the personalization and drag the bookmark icone again to the bar.

For the Bookmarks if you press it and visite the same page at the end of the address you will have a yellow star, if not is on gray all the bookmarks that you press will go inside of the menu of them.

press ALT then press bookmarks same thing!

You may have removed the button(s) from the Navigation Toolbar by accident.

If you right-click a toolbar item in normal (non-customize) mode then you can remove this item from the toolbar.

• "Remove from Toolbar" will remove this item from the Navigation Toolbar and moves it to the Customize palette ("3-bar" Firefox menu button > Customize)
• "Move to Menu" will move this item to the "3-bar" Firefox menu button drop-down list
• "Move to Toolbar" in the "3-bar" Firefox menu button drop-down list will move this item to the toolbar

Open the Customize window and set which toolbar items to display.

• 3-bar Menu button > Customize

• if missing items are in the Customize palette then drag them back from the Customize window on the toolbar
• if you do not see an item on a toolbar and in the Customize palette then click the Restore Defaults button to restore the default toolbar setup

• https://support.mozilla.org/kb/customize-firefox-controls-buttons-and-toolbars