Gravity Forms v1.6.3 Beta 2
My form doesn't show in any version of Firefox I've tested (versions 10.0, 8.0.1 and 3.6).
It shows in all other browsers I've tested including Chrome, IE8, and IE7.
If I disable javascript the form appears, and also (interestinglly) when I remove wp_head() and manually add jQuery to my WordPress header. Which narrows the problem down to a plugin, or something WordPress itself is outputting in wp_head.
Only plugins used are Gravity Forms (with no additional add ons) and WP-PageNavi (which should affect markup only — and in my tests doesn't make any difference if it's disabled).
The form appears for a fraction of a second before disappearing, and inspecting the form with Firebug shows the form is actually getting replaced with (I think) an empty submission message:
<div id ="gforms_confirmation_message" ... ></div>
Is it possible something (in Firefox only) is triggering the form submission behaviour?
Form is in the RHS column at the bottom under the SUBMIT heading: httpster.net
—Dom