Ok, well I have searched every nook and cranny of the internet and I  still have yet to find a practical solution for this.  It is absolutely  unbelievable that Google has not offered programmers a way to do this,  or to fire actual events on the page properly.

I have an ecommerce form where every necessary field for checkout is on one page, however for tax to be computed properly I need to know when the state has changed.  If the user has Google toolbar installed and uses the Autofill option, the only way I know of right now to check for that is to set a javascript timer to run every X number of seconds to look for changes and manually fire the ajax event.  Additionally, Firefox seems set the selectedValue if the user is just hovering instead of actually selecting it so when I compare the selected value to the hidden value, if the user has the dropdown open and is scrolling through the states, the event will fire because the  user is hovering over a value.

I am at my wit’s end and I can’t believe that the developer community has stood for Google completely bastardizing the webform process and not providing a way to gracefully handle events.

Any direction someone could provide on properly disabling the autofill feature, or handling it correctly (in Firefox [I can do this in IE already]) would be much appreciated. I have tried !important tag, changing the field input colors, renaming the field to something  insignificant, etc etc.

I am frustrated that I have a very graceful and elegant solution to a real world problem however I am being hampered by this ”supposedly” useful application.

Update (partial solution):

So while not 100% perfect, I was able to rename my state dropdown field (the one I needed to trigger the ajax computation for sales tax) to something completely arbitrary (i.e. taxExemptStatus).  In addition, I also had to put a . after the values in the dropdown. It wouldn’t work unless I did both these items.  I guess the autofill uses both field name and value options to determine if it can fill the field.  A lengthier discussion is available here: http://forums.asp.net/t/1198547.aspx