There is a minor bug in the javascript code for hiding/showing categories. When you click to hide an entry in the cookie is stored as |cat3|. But, when it is displayed again, the cat3 is removed, but the || are not. So, after many hide/shows you will get a cookie that looks like ||||||||||||||||||||cat3|||||||cat2|||||||||||cat1|. This can eventually get too large to function. It is easy to fix.
In ubb_jslib.js
In the function showHideblock(), at the very end before the setcookie statement, you can add the following code.
var intIndexOfMatch = newCookie.indexOf( "||" );
while (intIndexOfMatch != -1){
newCookie = newCookie.replace( "||", "|" );
intIndexOfMatch = newCookie.indexOf( "||" );
}
