Benchmark: getElementsByClassName vs querySelectorAll

HTML Preparation code:

<style>.searchMe {border: 1px sold red;}</style>
<table id="tableTest"></table>

Script Preparation code:

for(var i=0; i<10000; ++i)
{
  var cell = tableTest.insertRow(-1).insertCell(-1);
  if(i%2==0)
     cell.classList.add('searchMe');
}

Tests:

getElementsByClassName
var found = tableTest.getElementsByClassName('searchMe'); tableTest.rows[0].cells[0].textContent = found.length;
querySelectorAll
var found = tableTest.querySelectorAll('.searchMe'); tableTest.rows[0].cells[0].textContent = found.length;

Rendered benchmark preparation results:

Previous results

Test case name	Result
getElementsByClassName
querySelectorAll

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Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0

Browser/OS: Firefox 91 on Windows

Test name	Executions per second
getElementsByClassName	224153.1 Ops/sec
querySelectorAll	8944.1 Ops/sec

getElementsByClassName vs querySelectorAll (version: 0)