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I read How to add defer="defer" tag in plugin javascripts? and the code @toscho posted works good to defer certain js files or deferring ALL js files by commenting out the contact-form-7 line, but I need to defer all js except 1 or 2 files. I for sure need to exclude jquery.min because it causes the Revolution Slider plugin to stop working when it's deferred.

So how would I write a conditional in the following code to exclude certain js files? For example if I wanted to exclude jquery.min and jquery.ui.core.min

function add_defer_to_cf7( $url )
        if ( // comment the following line out add 'defer' to all scripts
        FALSE === strpos( $url, 'contact-form-7' ) or
        FALSE === strpos( $url, '.js' )
        { // not our file
            return $url;
        // Must be a ', not "!
        return "$url' defer='defer";
    add_filter( 'clean_url', 'add_defer_to_cf7', 11, 1 );
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tumbleweeds No one? :) –  Nate M. Apr 3 at 2:52

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