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CloseReview for CardBook by 27in-iMac
Rated 1 out of 5 stars
Mac Sierra 10.12.6 - Thunderbird 52.2.1 (64 bit)
Disabled then Enabled Add-ons until I found the culprit which was hiding the red, orange and green menu bar buttons
this is fixed in the current 21.1... sorry...
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