I have the following simple simple test script: 
use WWW::Mechanize::Firefox;
my $mech = WWW::Mechanize::Firefox->new(
  launch => '/Applications/Firefox.app/Contents/MacOS/firefox',
);

$mech->get('http://google.com');

[download]
I'm on Mac. The above script works fine when the FF app is completely closed or when an existing instance of FF exists. However, on a Mac, it's possible for the application can be running without having any windowed instance of FF displaying. And when I run the above code without an windowed instance of FF, I get the following error: 
I, MOZREPL : Client connected : 127.0.0.1:57788 : chrome://browser/con
+tent/hiddenWindow.xul
Can't call method "addTab" on an undefined value at /Library/Perl/5.12
+/Firefox/Application/API40.pm line 131.

[download]
I was told this was the place to go for support for this module. Let me know if SOPW isn't the right place.

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In reply to WWW::Mechanize::Firefox throwing error when launching a new Firefox instance on Mac by nysus

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