Maybe it works if you enable the window title bar.

You can make the title bar visible via the "Title Bar" button at the bottom left in the Customize palette window.

• "3-bar" Firefox menu button > Customize
• View > Toolbars > Customize

See also:

• https://support.mozilla.org/kb/learn-more-about-the-design-of-new-firefox
• https://support.mozilla.org/kb/common-questions-after-updating-to-new-firefox

That worked. however does that mean anytime I want to move the browser window I need to show the title bar? ..surely this is a bug and not by design!!

You can try to open the system menu via Alt+Space and use the move menu item. Dragging a window is only possible via the title bar, so that isn't possible when the title bar is hidden.

That does work, and will suffice for the moment....but it seems silly that I'd have to do that every time to move a window. I'm sure it will go away with other bugs. Thank you for your help!

driemer said

I cannot drag the firefox window. any ideas?

I have same (recent) problem on Mac/Yosemite

driemer said

I cannot drag the firefox window. any ideas?

I have this problem as well, but only with the "Private" window. I am able to move the regular one.