WWW::Mechanize::Firefox throwing error when launching a new Firefox instance on Mac

nysus has asked for the wisdom of the Perl Monks concerning the following question:

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.

$PM = "Perl Monk's";
$MCF = "Most Clueless ~~Friar~~ ~~Abbot~~ ~~Bishop~~ ~~Pontiff~~ Deacon";
$nysus = $PM . $MCF;
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Re: WWW::Mechanize::Firefox throwing error when launching a new Firefox instance on Mac by Corion (Patriarch) on Feb 28, 2013 at 13:14 UTC
This is most likely a bug in WWW::Mechanize::Firefox. I guess that it finds an existing `navigator` window but that this window is hidden on the Mac and does not allow new tabs to be created in it. I'm not sure how to debug this as I don't have a Mac, so in the meantime the workaround will have to be that you launch Firefox separately and ensure that at least one window is open.	[reply] [d/l]
Re^2: WWW::Mechanize::Firefox throwing error when launching a new Firefox instance on Mac by nysus (Parson) on Feb 28, 2013 at 13:45 UTC
Thanks for your help. After some trial and error, I found the following workaround to the bug: `$ff = Firefox::Application->new( launch => '/Applications/Firefox.app/Contents/MacOS/firefox', ); $ff->quit( restart => 1 ); # restart sleep 2;` [download] This launches a new FF application no matter what, then restarts it. Then I found you have to sleep for a bit before you can call WWW::Mechanize::Firefox->new and go to work browsing in the tab. If there is a way I can help you troubleshoot this, let me know. I've got a spare mac and I can give you control over it in a guest account via vnc. Maybe that would work. $PM = "Perl Monk's"; $MCF = "Most Clueless ~~Friar~~ ~~Abbot~~ ~~Bishop~~ ~~Pontiff~~ Deacon"; $nysus = $PM . $MCF; Click here if you love Perl Monks	[reply] [d/l]