I installed NoScript, had it open its own painfully-flashing website, and uninstalled NoScript.
I currently use (1) QuickJava, (2) Ad Block Plus, (3) Toggle Animated GIFs, mainly to distinguished animated gifs from other images and avoid accidentally reblogging pain on Tumblr, and (4) Stylish, after someone suggested a fix to block Tumblr video on that site.
I also use a couple bookmark fixes and other tools.
I still have trouble with animation on the Guardian unless I disable Javascript, with hard-to-navigate and flashing menus on some sites, and with auto-zooming and flashing maps on some sites.