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<?php echo 'blah'; session_start();
Output for 7.2.0 - 7.3.1
blah Warning: session_start(): Cannot start session when headers already sent in /in/42shF on line 6
Output for 7.1.25
blah Warning: session_start(): Cannot send session cookie - headers already sent by (output started at /in/42shF:2) in /in/42shF on line 6 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/42shF:2) in /in/42shF on line 6