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

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  • Last reply by cor-el

rabenson72
rabenson72
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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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cor-el
cor-el
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Maybe check: