My latest Google maps lookup template was not working in Firefox 3.n. It was working fine in IE 8 (and 8) so I thought maybe IE was compensating for some shaky JavaScript code, and 'working out' what I was trying to do and fixing it for me.

After spending half an hour painstaking going through my Google JavaScript and removing everything out of my FuseBox framework, just in case anything was mysteriously interfering, I was at a dead end.

A quick flick around online and it seems that there is a setting in FireFox that blocks this sort of functionality.

1. Type 'about:config' (without quotes) in the browser's address bar.
2. Type 'image' (without quotes) in the 'Filter' field.
3. Verify that 'dom.disable_image_src_set' is set to FALSE.
4. Verify that 'permissions.default.image' is set to 0 (the default setting).

For some reason in my FireFox installation the 'permissions.default.image' was set to 1, which blocks the function return from Google.

Google has a tech note on it here:

http://maps.google.com/support/bin/answer.py?answer=18529&topic=10789

It is really frustrating when 'controls' are set outside of the development environment. Now to put all my code back!