固定后的螺丝宽度

I'm trying to script a little chat for my website. I'm using jQuery, bootstrap and ajax requests for this.

Fiddle

After appending the new <li> the width is totally screwed for the appended element. Hardcoding the size won't help.

Thanks in advance for any help.

Sry guys, really messed up my question. It had nothing to do with the append();

Just happens with a string longer than 24 chars.

So I just did:

$content = chunk_split($content, 23, "
");

Thanks anyways.