Javascript string concatenation performance on modern browsers: array.join("") is now slower!

Well… as many Javascript developers know, a common practice to handle big string concatenation, is to implement a sort of  “stringBuffer” by using an array as data container and then convert it to a string by using the method join(). Ie:

var buffer = [];
var target = document.getElementById("box");

for (var i=0; i<10000; i++) {
    buffer .push(['<p id="node_', i, '" id="node_', i, '">Content ', i, '</p>'].join(""));

target.innerHTML = buffer.join("");

This is theoretically the fastest way to manage huge strings and to speed up the building of dynamic content.

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