Say I have a site that's centered on the page, and do $ ("#some_content").slideDown(). If the appearance of the new content means that the page no longer fits in the browser window, scrollbars will appear, and so the available page width decreases slightly, and so my centered content jumps left while it's sliding down.
Is there a decent workaround for this? Best I can figure out at the moment is to persuade the browser to always display scrollbars, which isn't exactly ideal.