There are two places you might mean:

• Bookmarks Toolbar
• Button that displays a drop-down of the Bookmarks Menu

On the first one, try this:

orange Firefox button > Options > Bookmarks Toolbar or
classic View menu > Toolbars > Bookmarks Toolbar

On the second one, which bar was it on? There is a slightly complicated interaction of menus and that button. When the current interface was developed, various UI people decided to ruthlessly eliminate all unnecessary or duplicative items. Therefore, when the classic Menu Bar is displayed with its full Bookmarks menu, the Bookmarks drop-down menu button is suppressed from the Navigation toolbar. If the button is on the Bookmarks Toolbar, however, it is not suppressed from there.

Or... if your entire classic menu bar is missing and replaced by the orange Firefox button, you can switch between them using:

orange Firefox button > Options > Menu Bar or
classic View menu > Toolbars > Menu Bar

To temporarily display or activate the menu bar, you can tap the Alt key.

Hi, Thank you. that's the answer, it will save the remainder of my thinning gray hair.

Or to access the bookmarks you can click Ctrl+B