When I click to open Firefox I get this message: "A copy of Firefox is already open. Only one copy of Firefox can be open at a time." What should I do to prevent this?
No matter whether I click on the icon on the dock, or the icon in my applications folder, I've been getting the above message ("A copy of Firefox is already open. Only one copy of Firefox can be open at a time.") for more than six months, so I've had to resort to using Safari as as browser.
No matter whether I click on the icon on the dock, or the icon in my applications folder, I've been getting the above message ("A copy of Firefox is already open. Only one copy of Firefox can be open at a time.") for more than six months, so I've had to resort to using Safari as as browser.