Instead of using the feature in Textastic, you can reference Firebug Lite directly in your html file as described at http://getfirebug.com/firebuglite#Stable:

<script type="text/javascript" src="https://getfirebug.com/firebug-lite.js"></script>

This way it will be loaded with the web page.

Textastic for Mac is now available on the Mac App Store: https://itunes.apple.com/us/app/textastic/id572491815?mt=12

We seem to have similar workflows. SourceTree is my tool of choice, too. I think SCM integration is currently out of Textastic's intended scope.

I'm using Marked, too. You can simply drag the file icon from the window title in Textastic onto the Marked icon. It works excellent.

That one is on my todo list. I'm missing it, too :)

I'll have a look at how this can be done for a sandboxed Mac App Store app.

Which command would you prefer? "textastic" or something else? (TextMate uses "mate" for example)