Opening a webapp from the dash opens a new browser window

Overview:
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What was expected:
-opening the dash and selecting a webapp, say, facebook would open facebook in a new browser tab
What happened instead:
-launching facebook from the dash opened facebook in a new Firefox window

Reasoning:
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I think that -- to provide the most fluid user experience possible -- that webapps should open in a new tab of the main browser window on the current workspace. It is enormously inconvenient to have the facebook web app open, then decide to go back to my main browser window and have to click to bring up the spread and then select the proper window. The problem is amplified when I have multiple webapps open (facebook+tumblr+launchpad, etc.) and have to sift through a number of browser windows in spread mode just to find my actual one. On top of this, going to a webapp via web browser (ie, typing facebook.com into Firefox's awesome bar) does not open a new window, but rather a tab. This gives the whole "webapp experience" a very inconsistent feel.

Scenario:
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An inexperienced user has just installed Ubuntu and is trying it out. They open Firefox, and (naturally) immediately log into facebook. Facebook asks them to install their app as a webapp, and the user thinks this is cool and clicks yes. Facebook installs, the icon appears in the launcher, and that's that. The user then goes on to browse the web.
The next time the user boots up and logs in, they open up firefox to browse the web. After a little while, they decide to go on facebook, and follow the offically endorsed workflow: hit start -> type "facebook" -> click the icon. Facebook opens in a new window. They now have TWO browser windows open, whereas last time they did virtually the same thing they only had one. They'll inevitably end up googling stuff from tabs in the facebook window, until their internet experience is a mess spread out over multiple browser windows.

Solution:
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My proposed solution is this: webapps are simply shortcuts to tabs in the main browser window. If a user want their app in a new window, they can drag the tab out into a new window manually (it is easier in Firefox to do this than the opposite). If you want to go to facebook, you just click the icon and it takes you to the tab, easy as pie. This will also make switching back and forth between a website, a webapp and a desktop app much easier: only one click per switch (ex: click facebook icon to get to facebook -> click ubuntu.com to get to Ubuntu website -> click gedit icon to get to gedit).

I've done some looking into the code for the package and have come up with some possible modifications, but I'm not sure how to go about patching and testing on my system before submitting, so I guess I'm limited to just this bug report.