A.  user_pref("javascript.classic.error_alerts", true);

B.  user_pref("javascript.classic.error_alerts ", false);

C.  user_pref("javascript.console.open_on_error ", true);

D.  user_pref("javascript.console.open_on_error ", false);

Correct Answer :
user_pref("javascript.classic.error_alerts", true);
Explanation :
No Explanation available for this question
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