I'm trying to configure Firefox to use a specific application. In order for the app to run properly, the tech support personnel state I need to go to "about:config" and change the value of "dom.url.getters_decode_hash" from "false" to "true". When I configure it, users launch the app but the value change isn't modified.

Is there a file that needs to be modified, such as mozilla.cfg and if so, what would the proper parameters be to set the value?