Firefox extremely slow at clearing tables

I'm testing my code that works with dynamic tables in Firefox. The tables I play with are ~1000 rows long and get generated from search results that are in JSON via templating engine.

The resulting string is like <table><thead>... and then I place the table into a placeholder element like this: $('#holder').html(str).

The first search gets rendered fast, where as the following ones are extremely slow. And it seems that most of the time takes placeholder clearing.

That is, if I place $('#holder').html("") or $('#holder').empty() before placing a new table, then this clearing takes much time and the rendering of the new tabl开发者_如何学JAVAe itself is as fast as it was.

Speaking about the numbers, rendering takes only 90 milliseconds whereas clearing takes 16 seconds.

I wrote this jsfiddle: http://jsfiddle.net/cJGR3/2/

If you press "Test me" consequently, you will notice that clearing will take most of the time.

How can I solve this issue?

As pointed out by DanielB, Firebug was the reason.