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I have heard from several people that <?= has been re-purposed / replaced in newer versions of PHP, but am unable to find supporting documentation to this change, or to what version(s) it effects. Has short echo been replaced or re-purposed and is there supporting documentation to it?
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The current documentation does not reflect any change of behaviour of shorthand echo (<?=) since version 5.4.0, in which only the necessary configuration to enable it was changed.