"Open page under" Is that its name? What should it be doing?

Are you looking for a menu command to open a file from your computer? I don't know where that moved to!?!

Here are some other options:

• The keyboard shortcut is Ctrl+O
• There is an optional toolbar button available in Customize -- see Customize Firefox controls, buttons and toolbars
• On the classic top menu bar (File, Edit, View), it is on the File menu -- you can tap the Alt key or F10 to show the bar temporarily if you don't want to show it permanently

jscher2000, I called "Customize Firefox controls ...". It worked. Many Thanks Rainer