You can move the Home Button (as well as the back one page and forward one page) button to the tab bar customize the Firefox interface more to your liking.
1. Open Firefox.
2. Right-click on the toolbar (where the Home button is located by default) and select Customize.
3. Left-click and drag the Home button to the far left portion of the tab bar.
4. Release the left-click and the Home button will now be located on your tab bar.