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Mac message "Can't open Firefox. Only one Firefox can be open at a time."

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  • 1 has this problem
  • 4 views
  • Last reply by cor-el

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We had problems completing IRS fillable forms on our Mac. After processing a major update on the Mac, we tried to open Firefox, but instead got the message "A copy of Firefox is already open. Only one Firefox can be open at time." The Firefox we are trying to open is the only one there.

We had problems completing IRS fillable forms on our Mac. After processing a major update on the Mac, we tried to open Firefox, but instead got the message "A copy of Firefox is already open. Only one Firefox can be open at time." The Firefox we are trying to open is the only one there.

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