You should be able to click the "x" on the individual tab to close just one.

Hope this helps!

My problem isn't that I can't close a tab (either by clicking the 'x' or by right-clicking on the tab and selecting Close Tab), it's that I can't find a way to close a window.

If the window has removed the red "X" in the right corner, or has hidden the File Menu. Try pressing

• CTRL+SHIFT+W closes a FF window
• CTRL+W will close the active Tab.

As for 'Close Window' option within the File menu, it says "Exit"

If that doesn't help: Maybe screenshot the window, and post it here so that we might be able to see what you are referring to

Thank you, CTRL+SHIFT+W does the trick. (Clicking the red 'X' in the upper right corner or clicking File/Exit exits FF, closing all windows and tabs. My question was how to close an individual window without closing other windows/tabs. I see CTRL+SHIFT+W does that, though it still surprises me there's no way other than a keyboard shortcut to do that.)

If a window is created by a website that intentionally hides/removes the Menu and Close button then its due to that website.

Please be sure to make your Question as "Solved"

The problem isn't a particular website hiding or removing a Close Window option. In no window, including ones I create myself, do I find a Close Window menu right-click option. So far only thing that works is your CTRL+SHIFT+W option. For which I'm grateful, but again, I find it strange that the only option is a keyboard shortcut. But I will mark my question 'Solved.'

Some menu entries in the main menu bar are hidden if you use the mouse and only appear if you use the keyboard to open the menu (Bug 626825).

You can see the difference if you use Alt+F to open the File menu or other menus like the Edit menu (Alt+E) and Bookmarks menu (Alt+B) and compare that to what you see if you use the mouse to open the menu after you have made the menu bar visible by tapping Alt or by pressing F10.

Add code to userChrome.css below the default @namespace line.

• http://kb.mozillazine.org/userChrome.css

The customization files userChrome.css (interface) and userContent.css (websites) are located in the chrome folder in the user profile folder.

• http://kb.mozillazine.org/Editing_configuration

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */

/* Always show menu entries with class="show-only-for-keyboard" */
#navigator-toolbox menuitem[class="show-only-for-keyboard"] { display:-moz-box!important; }