Over the last days I did some small steps to clean up the code of my TYPO3 imagemap extension. During that process I wanted to update jQuery from 1.2.6 to 1.3.2. Initially this went fine but after some testing I found this strange error:
[Exception... "'Syntax error, unrecognized expression: #' when calling method: [nsIDOMEventListener::handleEvent]" nsresult: "0x8057001e (NS_ERROR_XPC_JS_THREW_STRING)" location: "<unknown>"
Due to the verbosity of the message (location “” ) it wasn’t obvious for me that what’s going wrong. But right after I found the jQuery-bugtracker log #4323 ($(‘#’ + myID) throws an exception in version 1.3.1 and 1.3.2 if myID is a zero length string) everything was clear. For some reason they’ve made the decission to add some strictness to their API so for the future always validate your selectors before you ask jQuery ;)