>How can I see the whole data available to the browser in FF, similar to ChromeDev Tools

It's a lot different than what chrome does, but I believe they're integrating the resources with the network tab: (scroll to the bottom where the pie charts are.)

https://developer.mozilla.org/en-US/docs/Tools/Network_Monit...

> Cannot install nightly versions on customers

Do your customers develop web pages? If so why are they paying you to install a browser?

>But not yet on the Scratchpad

This appears to be true.