Failed to jump to next part

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Both Angular 1.2 and 1.5
Firefox Version 49.0a2
Build ID 20160711004013

Chrome is fine.

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It happens randomly.

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https://bugzilla.mozilla.org/show_bug.cgi?id=887695
https://bugzilla.mozilla.org/show_bug.cgi?id=354358

http://unixpapa.com/js/testkey.html

Chrome:

Firefox:

IE8:

IE9+:

IE9+, first launch: