If you accidentally set a variable to a dropdown element, instead of the value, and then try using a conditional expression on it, Safari crashes.

Example:

myVar = $('#myDropDown'); //Note that .val() is omitted

if (myVar == 0) {
  doSomething();
}

Obviously this is my fault (or any developer) for not being careful. But it shouldn't crash the browser. Firefox gives the following error:

Error: uncaught exception: [Exception... "Illegal operation on WrappedNative prototype object"  nsresult: "0x8057000c (NS_ERROR_XPC_BAD_OP_ON_WN_PROTO)"  location: "JS frame :: http://localhost/npsd/common/js/jquery-1.4.2.min.js :: f :: line 132"  data: no]